Category Archives: Projects

January 21, 2016 · 5:07 pm

Beware of the New RadioShack

(or, Things Aren’t What They Used to Be)

 

radioshackbattery

Radio Shack AM “Battery” Radio, circa mid-1970’s. Remember the “free battery club” cards?

My love of Radio Shack (now RadioShack) started in the 1970’s, when I discovered them in junior high. They were a place of wonder, where you could seemingly get a device or parts that would allow you to do damn near anything. The annual catalogs were my “wish books” and I spent hours poring over them. I even had, at one point, a constantly-updated list of three stereo systems in different price ranges that I would buy from them if I had the money. My paper route soon enabled me to start building one of those systems. When high school graduation time arrived, I landed a job with them and stayed for over five years. (That introduced me to the ugly side of working retail, but that’s a story for another time.)

I kept up with them when I moved on and still shopped there, but over time that decreased. I watched anxiously when news broke of a possible bankruptcy in late 2014, and I held my breath during the months to follow. The local store closings brought the ability to get some great deals but I didn’t want to see the company disappear. Let’s face it—many of us may have liked their stuff but knew it was foolish to buy until there was a sale. Their prices weren’t the greatest but if they had something no one else had, we were stuck paying retail. When the news finally came that their stores would still be around but in fewer numbers and under different ownership I was relieved.

But, as you’d expect, there were some ‘gotchas.’

Their web site took literally months to bring back online. The store personnel who remained in the new company always looked shell-shocked and didn’t always have the most current information about what they had in stock or what would be available in the future. In the stores where Sprint was to occupy about a third of the floor space it often took months (again) for them to arrive and set up shop. The stores still had an air of uncertainty about them as the pieces of the explosion slowly settled. I thought that everything, once finished, would be kind-of like it was.

Then came what I call “Scannergate.” First, some history is necessary.

For many years before the bankruptcy a company named GRE made scanning radios for RadioShack. They were a great product that worked well and I lusted after a desktop digital trunking model called the PRO-197. GRE closed up their business and stopped making scanners for RadioShack in 2012. The next year Whistler Group acquired GRE’s intellectual property and re-opened one of their factories to resume producing scanners for both themselves and RadioShack. The current-model RadioShack PRO-652 and Whistler WS1065 were said online to be internally and functionally identical to the PRO-197.

During the liquidation I purchased a PRO-652 scanner that was a display unit, and some months later I stumbled across an earlier PRO-197 from another source. The PRO-197 had a problem in that the combined volume/squelch/power control was noisy. I disassembled the unit to discover that the part was a completely sealed unit—there was no way to clean the control with a cleaner/lube spray. The scanner would need a new part and I thought it would be a simple problem to resolve. RadioShack operated a National Parts Department for decades where you could purchase nearly any part or service manual for an item that was under five years old, with some parts available even longer than that. In the recent past they changed the name to “RSU Online” and allowed their customers to order parts locally to have them delivered to their mailboxes. I went to one of the surviving local stores near me to place an order.

You can guess what happened next. I was told RSU Online was no more. An email to RadioShack Customer Care yielded this response:

“No, we do not have any of National Parts’ inventory left. I believe that product was liquidated months ago. We regret any inconvenience.

Thank you,
Adriana ”

They apparently had no information on whom, or what company, had purchased their parts inventory. I also sent an email to the bankruptcy court but they did not have that information either. I returned to the store and posed a series of carefully worded hypothetical questions to the manager. In the new RadioShack world:

• If an item fails within the warranty period the customer will be swapped for a brand-new unit.
• If a brand-new unit is not available (was recently discontinued and no stock remains) and the unit is still in warranty, they will be given a refund of the purchase price.
• They do not provide parts or repair services on any item they sold or currently sell. They might at some future point but not now.
• The customer may be able to obtain parts directly from the OEM (original equipment manufacturer) of that item if the manufacturer is known.
• Repair of non-warranty items would be performed at a local electronics shop of the customer’s choice at the customer’s expense.

Some of this makes sense—what choices do they have if they’ve sold off their repair facilities and the parts to do the work? On brand name items (such as Logitech) that OEM can provide parts and warranty service. However, for any RadioShack-branded product the consumer may likely find themselves out of luck when their expensive gee-whizzy breaks. RadioShack also makes a big assumption that most people won’t think about until they’re in trouble. If the customer’s item has a generic part that needs replacing (and they can find a local shop who does board-level repairs, which can be rare) they’re good. But if you need a custom LCD display, or a battery door, or a special-purpose IC chip, their precious piece of electronics is a paperweight.

In my case I knew that the OEM of my scanner, at least the newer one, was Whistler. There was a great chance that the PRO-197 volume control assembly was identical to the control in the PRO-652. No problem! I could just order a couple of controls from Whistler. I sent off an email to their customer service department and waited. After getting no response in a week I sent another email. Again, no response within a week. After a third email I heard from call center manager Mary Jo Duncan, who wrote,

“Unfortunately we do not offer parts for sell (sic) for the scanners.”

After we exchanged some emails and I made her to understand my unique situation, she told me to call back the next week and talk to Bryan, the lead scanner technical support person. When I reached him and explained the problem, I was told he needed to check with an engineer to verify that the newer product’s knobs would fit the older unit. That was the last time I could reach Bryan. I’ve left several messages for him, including the information that the knobs between the PRO-197 and PRO-652 are indeed interchangeable, but he’s never responded. It appears that he’s been informed of their policy and has decided not to continue our conversation further. By the way, when you call Whistler and are put on hold you get a message saying they can repair their scanners for a fee if you send them in. RadioShack units are not mentioned and, I’d imagine, older units like mine would be completely out of the question even if they did service them.

I now have a disassembled scanner in a box with no way to obtain a repair part and two companies that could care less, with one of them having the solution but are unwilling to assist. I’ve checked a number of parts sources online, including several places that offer to fix broken scanners. They don’t seem to have the part either.

I’d entertained the idea of purchasing the upgraded Whistler WS1095 but I won’t consider anything from them in the future. Granted, my situation is not a textbook, clear-cut problem, but you’d think they would help given that they still produce the scanner in question. If the way they’ve handled my issue is typical of their company’s attitude toward the end-user, I wouldn’t recommend their products to anyone.

As for RadioShack, well—I’m still cheering for them. But I wouldn’t recommend that anyone buy RS-branded products unless they have enough money to consider them disposable when they break.

If anything changes in the future I’ll post the information here.

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November 6, 2015 · 4:43 pm

Recovering Files from WebCT Zip File Backups

DI Zip Repair

My employer, a local university, used WebCT as its Learning Management System for years. WebCT’s user support was great when we originally adopted it, but that support grew poorer over time. We heard they were being purchased by BlackBoard, a company that had (at the time) even worse reports of poor customer responsiveness for smaller universities like ours. (I don’t know what their reputation is since the merger.) We planned a move to Desire2Learn, and backed up all of the existing courses in WebCT in case they were needed in the future.

Recently we tried to recover two of those old courses–one from 2002 and one from 2009. We’d used WebCT to make  Zip-formatted backups for us. Unfortunately WebCT modified those backups by altering the files it created so that Zip extraction utilities wouldn’t recognize them. Of course, if you wanted to recover those files in WebCT the program would happily read them and re-import their information. Which means you needed to have a working, currently licensed installation of the program. That’s an expensive proposition and is an unreasonable expectation.

I was asked to look at the problem; meanwhile, a co-worker took copies of the files home to try on his ancient candy-colored iMac. At one time he’d been able to extract WebCT backup files on that machine using the version of Stuffit Expander he owned. I threw a number of Zip file extraction programs at the files with no luck–all gave the error that the files were ‘damaged.’

The co-worker reported he’d had success using the old iMac/Stuffit combination. Since I was PC/Windows based and I knew we’d need a more modern way to recover the files in the future, I pressed on. It struck me that these programs all reported the same error–a corrupt file–so I ran them through a free Windows utility called DiskInternals ZIP Repair. The files were then readable and extractable by 7-Zip (my program of choice). After the co-worker compared my extraction and his, he said that my method recovered more files than his method.

If you find yourself in this situation, don’t hesitate to try DiskInternals ZIP Repair.

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October 18, 2013 · 10:23 am

Webcam. Digicam. Why Is There a Difference?

MicroShaftedMicrosoft purchased Skype, a free service, for $8.5 billion dollars a few years ago and the program’s users howled in protest. They’d seen that movie before, and knew about Microsoft’s “embrace, extend, and extinguish” strategy. Microsoft promised Skype’s users that they wouldn’t screw it up. A recent OS reinstall and upgrade of the program broke a major component for my employer though, and we’re not happy about it.

Let’s go back into time a bit. Several years ago we had a Polycom videoconferencing system installed in our conference room. We’d used it a lot in the past but the system had gotten old and the university’s gatekeeper wouldn’t support it anymore. We were quoted $15,000 to upgrade it. Department management weighed the cost against other needed upgrades and instructed me to dismantle the old system. I then purchased a Sony PTZ low-rez (NTSC) videoconferencing camera, Vaddio camera shoe and converter box, and a Grass Valley ADVC55 video digitizer. After installing two CAT-5 runs I put the camera on the upper back wall of the conference room and put the rest of the equipment in the presenter’s podium. The camera was then connected to the Mac through the digitizer with a FireWire connection. After also installing a Panasonic PJP-25UR USB conferencing microphone and Skype the system worked flawlessly.  We used it several times for online course sessions and job interviews, but mostly used the system for lecture capture using Tegrity. All was well with the world.

Last week we received a request for two remote connections into a workshop. Knowing Skype couldn’t handle it I decided to try GoToMeeting by Citrix. Meanwhile the podium PC needed a software upgrade so we allowed the campus IT folk to load a new image, after which I downloaded and reinstalled Skype as well as GoToMeeting. I first brought up GoToMeeting and the program couldn’t find our camera. Then I brought up Skype and it couldn’t find the camera either. Hmm. Time for serious troubleshooting.

I soon eliminated the cabling, digitizer, and camera as the source of the problem. I hooked the signal chain into the FireWire connection on a Macbook and got a great picture using different software. Then I hit the web. It seems that a number of people had developed the same issue after a Skype “upgrade.” Skype now only works with devices that identify themselves as webcams. After sending a Tech Support request to Citrix I discovered that GoToMeeting only supports webcams as well. Tegrity still works fine with the setup, so it seems that the support for my equipment is on a per-program basis and not at the OS level where it should be.

This makes no sense. I can (sort of) understand if Microsoft wants to derail businesses from using Skype in that manner since it’s a consumer product, but GoToMeeting’s stated premise is to allow conferencing with anyone, anywhere—and you’d have to believe that one of those locations would have a bunch of people at a big conference table.

It turns out there’s a workaround. Several companies offer software that allows a DV (digital video) camera to emulate a webcam. Programs such as ManyCam, SplitCam, TrackerCam, WebcamDV, and Webcam Studio (for Linux) are used for that purpose. Some of these have trial versions; some allow additional features such as titling and transitions. All of them require running their programs first, then minimizing them while you run Skype or GoToMeeting. You also have to go into each application’s setup menu and choose the camera “shim” software as your video source before your camera can be used. It’s not an ideal solution. I’d like to have a free program that performed the shim function silently, in the background, without all the other features that I don’t require.

I used to have a setup where someone could go into the conference room, boot up, launch the desired program, and they’d be ready to use the system. Now I have to be there to set up and tweak the system for them. Citrix’s GoToMeeting software has been around for a while, and it’s inconceivable that they still don’t support DV cameras.

As for Microsoft breaking something that already worked? Perhaps they’re finally learning some things from Apple…

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March 28, 2013 · 10:07 am

Some Weeks…

Android_BellyUp

…It ain’t easy being Geek.

I’ve had my Motorola Droid Razr Maxx cell phone for nearly a year and I love it. However, it shipped with an outdated version of the Android OS named “Gingerbread” when the next version, called “Ice Cream Sandwich” was already being rolled out. Verizon sent out the ICS upgrade within a couple of months; but by then the NEXT version, known as “Jelly Bean,” was being rolled out. I’d been waiting anxiously for JB for months when Verizon announced they were releasing JB a few days before Christmas last year. After a short time they stopped because the update was bricking their customer’s phones. (Oops.) Fortunately I didn’t get that upgrade. I settled back into waiting mode again and twiddled my thumbs.

Several weeks ago I heard that Verizon was rolling out JB again, this time for real. I checked for available updates on the phone and was told it was ready to download! I allowed the download (at about 40 minutes) and then attempted the upgrade. Everything looked good until I saw the picture of an Andy the Android on his back, chestplate open, with a red triangle with an exclamation point beside the hole in his chest. The phone rebooted and gave me a message that the update had failed. No reason given, just failure.

I went online and discovered that I wasn’t the only one. The main failure reason being posited was that the end user had disabled some apps on their phone. I’d rooted my phone after getting ICS and disabled a number of Verizon bloatware apps like their navigation service and music apps, so I re-enabled them and attempted the update again, still unsuccessfully. I was getting frustrated.

(Before I continue, a few words on rooting are called for. Rooting a phone gives the user access to areas of the phone’s operating system that they normally can’t get to. This allows a finer degree of control over how the phone operates. It also allows the use of utilities like “Titanium Backup” which allows me to make back copies of my phone’s data and apps. I also installed a WONDERFUL app called AdAway, which allows the blocking of streaming ads, including those within other apps. TB also allowed me to disable apps and, in some cases, completely delete them. Rooting also allowed me to transfer custom ringtones into the same directory where the phone’s ringtones are kept, which allows all ringtones to show up in the same list. I highly recommend the practice if you’re savvy enough to do it.)

Next, I decided to try a “sideload” installation, wherein you download an app (or an OS upgrade) and force an install from the phone’s SD memory card. I found the official Verizon Jelly Bean update and downloaded it, then tried connecting my phone to my PC after loading the necessary Motorola USB drivers. That was an exercise in frustration as I had to try several different sets of drivers. The phone had to be placed into USB “MTP” connection mode, and the PC didn’t find the necessary drivers among those I’d downloaded. After several hours I finally got the correct driver and Windows was happy. Then I copied the file to the phone’s SD card and powered the phone off. Then while pressing and holding the phone’s power button as well as holding down the Volume Up/Down buttons I got a special boot menu. I navigated to “Recovery” mode, and then chose the proper file on the SD card. The upgrade progressed as before, except this time I got verbose feedback on what was happening. The upgrade failed again (of course), but this time I got a long message with the phrase “assert failed: apply_patch_check” saying that the upgrade program couldn’t find an app called “Music2.apk.”  Now I was getting somewhere.

I remembered that I’d been playing around when I’d loaded Titanium Backup and used an option to completely remove a few programs. That had obviously been a bad idea. Now I had two options: I could either find the appropriate .apk files on the web (because I knew I’d get a different missing app error after this one was re-installed) or I could perform a “factory reset” and wipe the phone back to out-of-the-box condition. Because I didn’t want to do the latter, I found and installed a program called “Android Commander” on my PC. That program would allow me to look at the system file areas on my phone and copy programs into the normally-inaccessible system areas from the PC. Next I found and downloaded the missing Music2.apk file, used the file selection windows in AC to find the file on the PC side, then chose the appropriate directory on the phone side and tried to perform the copy.

Android Commander told me I needed ROOT level access. What? I was already rooted, you stupid program! Indeed, TB said I was rooted. Android Commander didn’t believe I was, and it wouldn’t allow me to copy a damn thing to the phone. An investigation led me to a FAQ on AC’s site that explained there were two types of root access. The first type gave apps on the phone itself root access to the phone’s system areas. The other type, which I needed and didn’t have, allowed access to the phone’s system areas from a connected PC. To get that type of access, the FAQ explained, I’d have to download the phone’s boot image, decompile it, change a line in a configuration file, then re-compile the boot image and upload it back to the phone. While I have some ‘mad skillz’ this is not one of them at this point in my life and I did not have the time to learn. By then I had gone into the next phase in my frustration, one that a careful geek avoids at all cost if they want to be successful.

I was pissed. I just wanted to load the damn OS upgrade, and I was tired of being denied. I decided to do the factory wipe. At least I had the foresight to load the Verizon Backup Assistant to dump my contacts to the cloud, but didn’t give a thought to my pictures or any other data on the phone. I was syncing with Google so that should be taken care of, right? I knew that my apps would automatically download back to my phone from the Play store so I believed I was set. I booted the phone again using the Vulcan Nerve Pinch, then chose Recovery mode and the option to do a factory wipe. I clicked through the warnings and let the wipe proceed. After all was done and I was back with a working phone with ICS again, I decided to attempt the sideload upgrade again. You can probably guess what happened next.

The upgrade failed. Again. With the same missing app error. When I deleted the apps from the phone using TB, they were completely wiped from even the backup image. I was right back where I started. Why the hell was this program attempting a selective “upgrade” rather than a complete OS install? Then I realized it was probably to ensure that the customer’s data was retained.

Now I knew what I needed. I’d have to find some way of installing the OS, this time as a complete load regardless of what was on the phone. It took a little while but I eventually found what I needed. A user with the handle mattlgroff on droidrzr.com had written a program called “Matt’s Razr Utility” that would do just what I needed. Version 1.82 is for the Verizon Razr and Razr Maxx ICS version, but I wanted to go right to Jelly Bean so v1.83 was what I needed. I downloaded and installed the program, then followed the prompts and connected my phone when told to do so. The utility did its magic, and in no time I was running Jelly Bean v4.1.2. Hooray, finally. Now I could re-install my apps, contacts, and calendar.

Well, my apps and contacts at least. It seems that the phone’s OS comes with its own Calendar app which stores information on the phone itself by default. The Google Calendar app, which is downloaded from the Play store, will sync with Google. I had inadvertently been storing all my schedule information on the phone and it was totally gone. I made sure to download the Google Calendar and set it up to sync with Google, then disabled (not uninstalled!) the phone’s calendar app. It took a while to re-enter my schedule but I was finally good. Over the next few days I had to open some apps and re-accept their terms-of-service as well as reset their preferences.

I also discovered that AdAway hadn’t re-installed. After more research I found that Google very recently had removed all ad blocking apps from the Play Store, sending their developers a notice that they had violated a clause in their Developer Distribution Agreement.  Apparently they didn’t like the fact that these programs interfered with the possible revenue stream from streaming and in-app ads. That explained why I couldn’t find Adblock Plus in the store either. Fortunately I discovered a link for the F-Droid App Repository which allows the download and installation of AdAway. Adblock Plus can be downloaded directly from the company’s website and sideload-installed, so I got that program next.

After going through this hell I now have my phone loaded with the “latest” version of the Android OS, Jelly Bean. I used the quotes because, as it happens, v4.1.2 is NOT the latest version of JB. Version 4.2 has increased speed and more features—and Verizon blew an opportunity to get their users current. Well, I’m done with waiting on Verizon. When I can find one of the Razr enthusiast sites that has version 4.2 of JB I’m going to install it. I might as well get used to it; I seriously doubt that the next iteration of the Android OS (known as Key Lime Pie) will be made officially available for the Razr / Razr Maxx.

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November 15, 2011 · 9:58 am

Trying for an HP Touchpad…

I noodled the idea of getting one of these beasts the first time HP had a “clearance” sale a few months ago but they were gone when I finally decided to get one. I have a couple of ideas for applications and thought I’d try my hand at programming for the WebOS platform. I spent time looking around for one but it seems the profiteers had beat me to them all. People were buying them up and turning them over for 100% profit on eBay. That was too rich for my blood and I shelved my idea.

Then HP announced they’d make a second and final run of these. It seems their decision to axe the platform greatly P.O.’d their strategic partners (suppliers), who’d invested a lot of money in making parts for the things. Aha! My second chance would arrive in the first part of November! I readied myself for the hunt…only to be disappointed again. This time HP’s retail partners decided to make some extra money. Most retailers like Best Buy, CompUSA and TigerDirect are either selling the tablets for double the sale price ($299) or selling them for the ‘real’ clearance price if you buy another HP computer or laptop at the same time. I call B.S. on this practice and hope it bombs. Who in their right mind would buy one of these for more than the original clearance price?

The problem for me is that I still have these app ideas I’d like to try. About a week ago I heard about a special HP program for WebOS developers…they were allowing people (and companies) who signed up for their developer program to buy up to two of the Touchpads for $149 each. Some undisclosed number of entities will be chosen to get “right to purchase” coupons that must be used by the end of November. I’ve signed up for the program (whose application deadline is 11/18) and am crossing my fingers. I want to make my apps available free, so some of the information requested on signup was off-putting (I suppose they assume only corporations who plan on making mucho bucks will apply). If I can get these, great–and if not, I suppose I’ll try developing my ideas for Android. We shall see…

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August 12, 2011 · 5:16 pm

Converting a Server’s SCSI Backplane to Use SATA Drives

I’ve wanted a huge network-attached storage box for years. Ever since I laid eyes on a small form-factor SnapServer that my employer demoed 10 years ago, I envisioned one of these on my home network. I wanted a single repository for all my media files and other data I wanted to share between my computers. Reality, and the availability of enough cash to fund the dream, kept me from realizing it.

I eventually landed a SnapServer 4100, a nice little 1U-high rack mountable box that could expand to give me just over 360GB of RAID-5 storage.  The on-board chipset could theoretically handle drives larger than 127GB, but a glitch in the OS meant that the proper driver to enable the chipset was missing. The OS could theoretically be modified to accept the larger drives but the manufacturer would have to do it—and they had no incentive to steal sales away from their newer, larger-capacity servers. Many people on the ProCooling forums have spent time analyzing and bemoaning the situation but none of them apparently have the chops to dump and disassemble the OS, then patch and recompile it for the benefit of all. (That includes myself, though I’ve often thought about poking around to see what I could do.)

UPDATE 8-26-2011: Phoenix32 and Terry Kennedy over at Procooling clarified what the issue was, despite some contradictory information they got from the people at SnapAppliance several years ago. The SnapServer 4100 used a different ‘Promise’ controller chip than other models at the time. Snap engineers did not believe it could handle LBA48 disks, meaning drives larger than 127GB. Depending on who you talked to, two changes needed to be made: one to the machine’s BIOS, and one to the OS to add the appropriate driver.  Add to that the server’s insufficient RAM expandability (which comes into play when the server recovers from a disk error) as well as the unwillingness of SnapAppliance to take sales away from their other units, and people decided it wasn’t worth the expenditure of their time and effort . Thanks, guys, for the information.

I gave up on going that route when I determined that the total expandability of the unit even with such a patch would only be 1 terabyte. I wanted more, much more—ideally I want a RAIDzilla, but I don’t think I’d ever use that much disk space.

I set my sights on piecing together a suitable server. I found a place selling surplus Intel SE7501WV2 motherboards and bought one. It’s more than powerful enough to be the heart of a NAS—it has dual Xeon 3.1 GHz processors, takes up to 12GB RAM, and comes with dual gigabit Ethernet ports. It also features a PCI-X high performance expansion bus that will accept a hardware RAID card. The board has on-board RAID support and originally came in two versions, one with SCSI RAID and the other with IDE RAID.  Mine supports SCSI RAID but I knew I wouldn’t use it as the drives are too expensive and available drive sizes are too limited.  At first I thought I’d get a generic multi-disk server chassis but realized I really needed the chassis designed for the board. I purchased a used Intel SR2300 from eBay and thought I was in business. It offers seven hot-swap disk bays and dual redundant power supplies. The hot-swap bays and backplane are SCSI to match the motherboard. I had the basic framework to build a server, but the supported drive type was incorrect. I was determined to make it work. Somehow.

 Inspiration Strikes!

I surfed the net hoping to find some conversion info. I just knew that someone else had to have travelled this territory before me and I was right. Mark Hoekstra’s GeekTechnique site detailed how he shoehorned some IDE drives into the chassis while leaving the SCSI backplane intact.  After chewing over the possibilities I decided I could convert the SCSI bays to accept SATA drives. I’d cut the SCSI connectors off the backplane and glue some combined SATA/power connectors onto the circuit board.  The connectors would include attached cables that would plug into a SATA RAID controller.  Power cables would be plugged into some sort of daisy-chain configuration and then go into the power supply. If I was careful I could keep the front panel connections that go through the backplane, as well as keep the combined floppy/CD-ROM drive assembly working. I was getting more excited as I began planning the mods.

After spending time in research I knew that I’d be losing some capabilities. The Intel chassis/motherboard combo’s hot-swap system can detect bad drives and cut their power to allow for a swap without taking the server down. An error status LED for that drive will light to indicate which drive needs to be exchanged. My version would require a power-down to exchange a drive. Ultimately that’s not a big deal as my server use isn’t mission-critical; I can afford a little downtime.

I decided to keep the original backplane as it was and modify a second backplane. Should I ever decide to get rid of the unit I want to provide the original accessories. (Not that anyone would want to go backward, mind you, but still…).  I visited eBay and purchased an identical backplane to hack on for $15.00 plus shipping.  While I was shopping I also purchased another empty drive carrier. The floppy/CD-ROM assembly could be removed after software installation and another drive put in its place, giving a total of seven drives in the array. I could also mount an eighth drive into the SCSI tape drive bay by using the filler tray. My goal for using the swappable drive bays was maintainability, NOT hot-swapability; if a drive goes bad I don’t want to disassemble the server to change it. Using the tape drive tray for another drive puts me right back to server disassembly, so eventually I’ll end up putting a USB-driven LCD status display in that bay.

The Roadmap

Since I’m using the existing backplane as a connector mounting plate the existing SCSI connectors had to go. To make the wiring neat I decided to tap the power off the board’s existing power jack, and run bus wires for each voltage and ground. This would allow me to clip the power wires short and tie them fairly close to the connectors. The SATA cables would be draped along the middle of the board in an effort to keep the existing cooling pass-throughs as open as possible. I knew that I’d lose some air-handling volume because the wiring had to pass from the board’s front side to the back through those holes.  However, since the drives I planned to use were more power-efficient and ran cooler by design the loss of air handling capacity shouldn’t be too big a problem.

Locating Parts

The biggest problem was in finding the appropriate drive power/data connectors. I installed a hard drive in one of the swappable bays and measured the amount of space between the drive’s back edge and the backplane. It worked out to be .35”. I needed a connector assembly whose body measured slightly less than that thickness. StarTech had a good candidate, but according to the technical drawings they sent me it was too thick. Several other manufacturers had similar products but they were also too thick.

Then I found CPUStuff.com.  They had two versions of the cable I needed, a ‘left angle’ version (part number 22SATAL) and a ‘right angle’ version (part number 22SATARS). Both of these have a straight data connector that will pass through the backplane’s cooling slots. The engineering drawings on their product pages told me they would fit on the board with approximately .066” left to fill. Perfect! I’d attach a shim to the connector’s back to fill part of the space and let the glue fill the rest.  Each assembly had a half-meter data cable which would work for all but one of the drive bays.  I ordered the number of cables I required plus a couple extra, and a SATA cable extender to stretch that one cable to the correct length.

I went back to eBay and found a used 3Ware 9550SX-8 RAID controller with a PCI-X bus. The card can handle a maximum size of 2-terabytes per drive, and came with a backup battery assembly for the card’s cache RAM. I also ordered four hard drives to start. I chose the Hitachi DeskStar 5K3000 HDS5C3020ALA632 (0F12117), which is a 2-terabyte SATA 6.0Gb/s unit with 32MB of cache. It employs “Coolspin” technology which means its speed varies between 5300 and 5900 RPM, and theoretically keeps the drive running cooler. Although the drive is capable of higher throughput than the card, its backward-compatible and if I decide to upgrade later I’m not limited by the drive’s speed.

Getting Down To It: Removing the SCSI Connectors

At first I tried desoldering one of the seven connectors. Each one has 80 pins, and as you can imagine the going was slow. I tried applying ChipQuick to a connector’s pins in an effort to lower the solder’s melting point, then applied heat from a hot air gun. The connector wouldn’t budge. If I’d had a hot air rework station things might have gone better, but lacking that tool, I used a Dremel cut-off wheel and removed each connector in two passes, shown in Picture 1.

Connectors hacked off, first pass

Picture 1. First pass at removing the SCSI connectors.

After this step I used flush cutters to clip the remaining plastic and pins from the connector side, then used the cutters on the reverse side to eliminate the sharp points. After this I tried once again to desolder a few pins to empty the holes; unfortunately the going was still too slow. I ended up using a Dremel grinding wheel to carefully level each pin even with the PC board. This makes the conductive pad larger if you don’t grind long enough; if you grind too much you go deeper and can sever or short PC traces. I realized that the connectors would need to be glued onto the board where other surface-mounted components were already attached. I surmised that they could be safely removed since they were adjacent to the connectors and probably related to the connector’s functionality so I unsoldered them.  After this step I cleaned the board of any debris, then plugged it into the server and did a power-on smoke test. No magic smoke escaped so I went to the next step.

Connectors off, vent holes enlarged

Picture 2. SCSI connectors off, some components removed, vent holes enlarged.

Attaching the New SATA Connectors

I held a data connector against one of the backplane’s air holes and realized I’d need to enlarge the holes just a bit to allow the connectors to pass through.  A Dremel cutting tool made this a quick job, and the result is also shown in Picture 2. Next I had to make the connector shims, and I’d purchased some .060” styrene plastic stock at a hobby store for that purpose. I measured a connector’s back side to determine the necessary shim size, and then marked the styrene stock with pencil with those measurements.  I used a sharp new razor knife to slice the styrene on a cutting mat. After trimming the edges to eliminate the ridge that formed after each cut, I mixed a quantity of JB Weld and applied a coating to the back side of a power/data connector. After pressing the styrene into the glue I clamped the assembly for eighteen hours and allowed the glue to fully cure.

Gluing the shim

Picture 3. Clamping the shim and connector while the glue dries.

Connector with shim

Picture 4. Finished connector / shim assembly.

Next, I pressed the connector onto a drive (which I’d already mounted into a hot-swap tray), spread a good quantity of JB Weld onto the back of the shim and mounted the drive into a drive bay. I had to carefully manage the cables from the connectors in order to prevent damage and avoid getting glue onto them.  After waiting the requisite eighteen hours I carefully removed the drive from the bay. I knew the glue bond was solid when I watched the backplane flex a bit when removing the drive! This backplane is around 3/64” thick, so flexing it is a feat. (I should also mention that you don’t want to swap drives often because the connectors aren’t designed for that.)

Connector glued on

Picture 5. A connector, glued onto the backplane.

I moved on to the next connector and repeated the process until all seven were done.  I left the wiring loose on the front side of the board while I moved on to the power bus lines.

Laying the Power Bus Lines

I sketched a general layout for where each power bus and the ground bus would go. I’d need two power busses: a +5 volt DC supply for the drive electronics, and a +12 volt DC supply for the drive motors. There were two +12 volt lines going to the board’s power connector since that current draw was so large, so that meant I’d need to run two +12 volt bus wires and divide the drive load between them. There were also two ground wires going to the power connector. I asked an electrical engineer friend if I needed to run two ground busses as well; in his opinion it wasn’t necessary. That made a total of four bus wires to place. I purchased some 14-gauge solid, insulated conductor wire for the busses. I wanted to keep the wire colors the same for consistency, but could only purchase red, black, and white wire. I solved the problem by placing yellow heat-shrink tubing over the white wire.

I envisioned that each line would stretch the width of the backplane and have pre-formed ‘dips’ in them.  These dips would allow the line to stand above the backplane to prevent shorts between the bus and any components on the backplane, while allowing wires to be routed underneath them. One end would be fed through a drive vent hole and soldered to the board’s power supply connector. The bus would be glued to the backplane with JB Weld to secure it by putting glue over the preformed ‘dips’ as well as at each end. Gluing the busses at the power connector end is important as the power connector stubs I soldered to are very short; gluing the wires at that end takes stress off the solder connection.

After measuring and cutting each wire, I started by bending the power supply end of a +12 volt line until the wire lay properly in place over its solder point. I then figured out where I wanted each ‘dip’ and bent it into each wire.  After I felt satisfied that the wire was formed the way I wanted it, I marked the jacket where I’d remove a small bit of insulation to create space to solder the drive power wires. A razor knife removed those small bits of insulation, and afterward I tinned each section to allow easier soldering.

Formed 12 volt bus wire

Picture 6. A formed 12-volt bus wire.

Close-up of formed 12-volt bus wire end

Picture 7. Close-up of 12-volt bus wire end.

I mixed a quantity of JB Weld and applied it to each bus wire’s ‘dip.’ I carefully placed the first wire and attached it with tape until the glue dried, then moved on to the next until they were all attached. You’ll notice that the glue points are sloppy. This is a consequence of applying glue with the shaft of a cotton swab minus the cotton tip. It’s difficult to be neat when using that method. Picture 8 shows the completed bus lines with the drive connections soldered on.

Busses done

Picture 8. Bus wires glued in place with drive power wires attached.

The final step was to solder the connector end and verify the connections with a volt-ohm-meter. The final touch was to cut some small pads out of sheet rubber I bought from eBay and glue them to the backplane under each solder point.  Contact cement was used to hold each pad in place.

Organizing the Drive Power Wires

I clipped the power connectors off each SATA power cable and fed the wires through the vent holes before feeding the data cables through. I fed the power wires to the places I would attach them and then clipped them a bit longer than needed. After stripping 1/8” of insulation from each wire it was soldered into place. Black RTV silicone was applied over the power connections to insulate them from accidental shorts.

Bus end glued

Picture 9. Bus wires soldered on and glued at power connector.

Drive wires attached

Picture 10. Drive power lines soldered in place.

To organize the SATA cables themselves, I resorted to trimming some self-adhesive 1” square cable mounting pads with a Dremel as shown in Picture 11. I carefully peeled the double-stick tape off the back side of two pads and applied JB Weld to glue them onto the backplane. I arranged the SATA cables to lay down the center of the board as a bundle and secured them with cable ties. Keeping the profile of these cables as low as possible is important as there are three powerful case fans about an inch behind the backplane. You don’t want to stop the fans from working (or allow them to chop up your cables). I re-installed the backplane into the chassis, then test-fitted the fans to ensure I had the proper clearance.

Wire tie pads

Picture 11. Wire tie attachment pads. Unmodified pad is on the left.

SATA cables dressed

Picture 12. SATA cables dressed and tied in place.

LED There Be Light!

After doing all of this surgery I realized I’d forgotten one little detail.  The 3Ware 9550SX-8 card has eight dual-pin connections for attaching drive LEDs. I wanted blinking lights! I posted to an Intel communities forum to see if anyone knew where I could get a schematic for the backplane. I thought I could use the existing surface mount LEDs for each drive and I was correct. Forum member Doc_SilverCreek  in the forum gave me the following information:

“Sounds like a heck of a project.  The LEDs are duel  (sic)/ bi colored LED packages hence the 4 legs. Pins 3 & 4 go to a 150 ohm pull up to Vcc. LED’s Pins 1 is the fault LED via an inverter (U3 & U5) and the back plane EPM7064 power driver controller (which likely is not working in your project). LED’s pin 2 in the activitive (sic) LED which runs directly to Pin 77 in the SCSI connector for each slot.  Hope this helps.”

So I knew where the LEDs were connected, but how could I connect them to the card yet make it easy to remove the backplane? My idea was to run wires from one side of each LED pair in a drive location to a walled ribbon connector socket glued onto the backside of the board. I’d have to remove the single remaining SCSI connector, seen in the upper-right corner of Picture 12, to make room for a cable connector. I’d also need to create a cable with a ribbon connector plug on one end to dual pin connectors on the other. I found the dual-pin connectors at DigiKey—these are commonly used in PC cases for front panel switches and LEDs. I could’ve recycled some of those but decided it was more trouble than it was worth. Spending under ten dollars for these connectors was definitely the right decision. Since these are non-polarized I could easily flip them if the drive LEDs don’t work when they’re first plugged in.

LED connector cable

Picture 13. The SATA card-to-backplane connecting cable.

Since the LEDs are normally connected though 150-ohm resistors to the backplane’s 3.3 volt supply, I guessed the resistor was being used for protection as a current limiter. I wanted to leave those in place. I’d need to solder one end of each wire pair to one end of an LED, and the other wire to the far end of the corresponding resistor. The problem: it was necessary to cut the PC board traces at each end of the LED as well as each end of the resistor to completely isolate the components from the board’s 3.3-volt supply and prevent that voltage from reaching the controller card. I cut the traces with a razor knife, then reconnected the resistor and LED with a piece of 30-gauge wire-wrap wire. After soldering each LED wire lead in place I used a bit of hot glue to tack them down and fed them to the ribbon cable connector. After soldering each pair I mounted the backplane into the chassis and used my volt-ohm-meter to measure the two pins from each LED/resistor and make sure there was 0 volts across them.

LED wires

Picture 14. LED connecting wires tack-soldered in place.

LED connector

Picture 15. LED connector glued to backplane.

LED connector top view

Picture 16. LED backplane connector viewed from top. Last 2 pins on left not used.

LED cable attached

Picture 17. SATA controller-to-backplane cable attached and threaded in place.

The board was complete! All that remained was to install hard drives and load OpenFiler, which I’ll document in a future blog post.

Things I’d Do Differently Now

This project involved a lot of experimentation, from removing connectors to laying bus lines and LED cables. Everything’s functional but not as neat as I like things to be. Knowing what I do now, here’s what I’d do differently if I were tackling this again.

1) Buy a hot air rework station.  It would be much easier to remove those stupid connectors with one of these babies. While I was at it, I’d remove as many other IC chips and components as I could to make running the bus wires easier and reduce the backplane’s current draw. That part would have to be done very carefully if I wanted to keep the seventh slot open for the CD/floppy drive. I wouldn’t want to remove any parts necessary for those and the front panel switches/LEDs to function.

2) Lay the LED wires first. There are a lot fewer of these and they’re more flexible in their placement. I could use insulated 30-gauge wire wrap wire and pass them from front-to-back of the board by using the (now empty) SCSI connector holes.

3) Use a syringe to apply the bus wire glue. I’d mix a good amount of the JB Weld and put it into a syringe (minus the needle, of course).  I’d have to attach them all at once before the glue hardened in the syringe.

Who knows? Maybe I’ll tackle version 2 this upcoming Winter with the goal of making it functional AND pretty…

A Thanks and Tribute

I would have loved to share the success of this project with Mark Hoekstra, but unfortunately Mark passed away on September 30, 2008 at the young age of 34. I’d like to think that he’d be proud to have inspired another modder to take his accomplishment to the next level. Without the inspiration he provided I wouldn’t have gone this far. Thanks, man—I hope to meet you someday on the other side, wherever that may be.

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July 26, 2011 · 2:16 pm

Auvio HD Radio Tuner Mod Improves Analog Output’s Sound

Several months back Radio Shack began clearing out their Auvio HD Radio tuners. These components provide HD Radio reception (both AM and FM) for your home stereo system. Its well laid-out front panel features a large backlit LCD for tuning information, a detented rotary tuning control with a divot for your fingertip to allow easy knob spinning, and other control buttons.  It even has an optical output in addition to the standard analog outputs!  It includes an IR remote and has provisions for rack mounting (!), going so far as to include the rack ears in the box. The units started out at just below $100.00 but had their price reduced to $39.95. That was pretty good, but customers could take an additional $10.00 off with a “$10 off a $40 purchase” coupon they were giving away with codes on their in-store receipts.  After checking stock on-line I visited the last store in my area that had them available and bought their last two units. I then purchased a third tuner from their website. The only tricky part came with getting a filler item to take the price over $40.00. When I bought the two tuners in store that was no problem as the total was over $40.00. Purchasing the tuner on-line would provide free shipping, but when I added a 99-cent pack of resistors to get the price up I invoked a $12.00 shipping charge! A complaint call to their website sales team gave me the price I wanted for both items and still gave me free shipping.

When I hooked the tuner up to my office stereo I was impressed by the unit’s look and feel during use, but its sound left me dry.  There was limited treble and the bass, while there, lacked any kind of punch. A quick online search yielded many forum posts complaining about the same issue. Supposedly the optical output yielded normal-sounding audio, but two of my amps only have analog inputs. I listened to the tuner occasionally for several weeks but found that I couldn’t listen long due to its lifeless sound. I had a hunch that the analog outputs had the wrong resistor/capacitor combination on the driver for the analog jacks, so I spent time searching in vain for a schematic for the unit. I had resigned myself to the prospect of having to reverse-engineer the circuit’s audio stage when I finally stumbled across a web forum post by user ‘vintageaudioexchange’ at the AudioAsylum forum. This promised to be a simple swap that would yield immediate improvement, so I ordered three of the Burr-Brown OPA2604AP chips from Digi-Key.  The post’s author claims the part cost him around fifty cents—I’d like to know where he got his op-amps. Digi-Key charges over $5.00 each for these little buggers.

Last weekend I decided to open up one of the tuners and try the mod. As you can see in Photo 1, the unit is what’s fondly called a ‘gutless wonder.’

Auvio inside view

Photo 1. The Gutless Wonder Exposed.

The power supply is hidden beneath a metal box for shielding; the board to the box’s right holds the op-amp to be changed, shown circled in Photo 2.

The chip to replace

Photo 2. The Chip In Question.

The stock op-amp is a JRE 4558, a low-dollar part that’s used to good effect in many products. Not so here!  I unsoldered the chip and tried to install a machine-pin DIP-8 socket. Unfortunately the row-to-row hole spacing is too far apart to use the better socket, so I installed a common, cheaper friction-fit socket before inserting the chip. While I was at it I re-touched the solder joints for the antenna inputs. The circuit board-mounted RF coax jack was the cheapest part I’d ever seen and was not attached to the back panel with the customary nut and washer. The panel hole is bigger than the jack itself although the jack is not centered in the hole. This creates a problem when a standard coaxial antenna cable hangs off the unit’s backside– the jacks’ bracket tends to bend. The jack can be seen in Photo 3.

Antenna jack

Photo 3. 'Stock' antenna jack mount. Note the space showing poor alignment.

Mounting a jack from the chassis in this manner is typically done to isolate the jack’s ground from the unit’s power and data ground connections.  However, unless the cable is light and the user carefully attaches and removes that cable you get a mechanically unsound connection.  Even if the jack is of higher quality the stress point is still moved to the PC board itself, which in my opinion is a poor idea.  I tested with a volt-ohm-meter and found all grounds to be tied together. I scoured my “hell box” and found some appropriately-sized nuts and washers, shown in Photo 4.

Mounting nuts and washers

Photo 4. Aw, Nuts (and washers)!

Since the PC board is mounted a short distance from the back panel, it would take two nuts to make a solid mount.  One of the nuts needed to be thicker than the other; this one would go on first and be screwed against the jack’s bracket. This filled the space between the jack and back panel.  (I could also have used a thinner nut and screwed it back off the jack to the point where it touched the inside of the case’s back panel.)  Washers were another story. The hole in the unit’s back was bigger than a standard washer for that size of connector. I found a few larger washers with solder tabs and used tin snips to cut the tabs off to make them appear like standard washers. The modified washer then went onto the connector from the outside of the back panel before attaching the second nut. This yielded a solid connection that protects the jack in case the cable gets jerked or pulled.

After re-connecting the unit I crossed my fingers and powered it up. While doing my research I’d found another thread where people were discussing op-amp swaps in audio equipment, and a poster cautioned that the resistor/capacitor filter values for the new op-amp might need adjustment since the new chip’s bandwidth exceeds the specs of the old part. I can report that this was unnecessary. There is a significant improvement to the sound—better high-end, improved low-end, and the sound is less fatiguing for extended listening. The original poster said he’s not the type to claim the difference “was like a blanket was lifted from the speakers,” but I will. The difference is that noticeable. I can now happily listen to my new acquisitions without constantly be bugged about their sound quality.

Additionally, I read that Best Buy sold a similar unit under the “Insignia” brand, the NS-HDTUNE. This tuner is reputed to have the same internal circuitry, so the op-amp swap should work on this tuner as well. These are still available as of today on the Best Buy website as an “outlet” item for $79.95; they won’t last long at that price.

I should also mention that, contrary to the logical extension that the “HD” in HD Radio stands for ‘High Definition” as it does in HDTV, it does not. It stands for “Hybrid Digital,” which is a trademark of its progenitor iBiquity Digital Corporation. A brief history of the format’s development can be found  here.

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March 30, 2011 · 2:33 am

Hacking / Modding the Bissell Little Green Cleaner

 

I bought my first Little Green Machine in 1994.  It was a first-generation, ugly, dark green box with one purpose: to suck up pet accidents and spills.  It was the only thing on the market at that time, and I desperately needed something to assist in cleaning up after an aging dog with bladder control issues.  It worked well, and I got several years’ use out of it for my $70.00 investment.  Eventually a plastic hose barb cracked inside the unit and I couldn’t find a replacement so I trashed it.  Bissell has always had a policy of refusing to supply internal repair parts to customers, thanks to paranoia about consumer lawsuits.

I purchased a newly redesigned model at that time—one that sort-of resembled an egg standing on its fat end.  It was a poor redesign with some flaws (like solution heaters that constantly failed) that I made do with for several years.  I must say here that Bissell was good about support.  After writing to complain twice about product failures, they replaced the unit both times at no charge.  The second exchange was for the first version of their 1400-series model (Figure 1) , which at the time was brand-new.

The Bissell Little Green

Figure 1. The Bissell Little Green.

I’ve been through three of these in the last six years.  After the first unit of the new series died, I began studying their design to see how I could service it myself (and extend its life a few years as well).  These things have gotten progressively more expensive, and my last replacement was priced just over $100.00.  For that amount of money I expect something to last longer than a year!

Quirks and Design Flaws

The first redesigned 1400-series model had a simple storage clip on its backside that you’d snap the hose’s sprayer wand into.  The wand was always popping out of the clip and hitting the floor, which would eventually crack the sprayer head and further decrease its already weak suction.  Other problems included: the solution heater would die, the sprayer would simply stop working, or would begin to clog after using the unit for six months or so.  The wand would drip cleaning solution after you finished using the unit and were putting the wand away.   Finally, the cleaner would develop a stench from the urine I’d be cleaning despite rinsing the unit‘s recovery tank after each use.  This is due to the way the recovery tank is designed.

Phew!

Figure 2. Tank areas that collect waste material.

You can see by looking at Figure 2 that there are a couple of problem areas (circled in red) near the recovery tank’s top.  These seem to collect material that eventually begins to smell.  Simply swishing hot water around in the tank is not sufficient to clean the areas, and you cannot access the tank’s insides to physically wipe the surfaces clean. The sprayer head and wand connection point was designed such that dirty water tends to collect in the nooks and crannies which also creates an unsightly, stinky mess.  This junction also provides a break in the air stream and contributes to the unit’s biggest problem– it simply doesn’t have much suction power.  The area you clean will remain fairly damp.

Design Improvements in newer models

I kept that original 1400-series model going for three years, by my estimates about two times longer than I should’ve been able to.  The fixes were fairly simple for a geek to do.  The recovery tank sat on a very thin rubber gasket that was glued to the main unit’s base.  This was in addition to the rubber gasket on the tank itself.  The base unit’s gasket began to wear away after a time, and I managed to make a replacement from some sheet rubber I purchased off of eBay.  I cracked the sprayer head attachment apart and re-glued the pieces together with five-minute epoxy.  I also glopped extra epoxy into the designed-in gaps and cracks while I was at it, which helped increase suction.  I finally had to retire the unit after trying to discover why its motor was whining so loudly.  After I took the unit apart to possibly oil the motor I learned more about the unit’s Achilles’ heel.

The currently-sold unit has several design revisions that seem to address some of the problems.  The wand clip on the unit’s back has been redesigned and includes a swivel arm that locks the wand in place.  Hallelujah!  No more dropped sprayer wands!  The sprayer hose has been changed from a solid green to a greenish-tinted clear hose.  This allows the user to see how much crap is in the hose (and tell how well the suction is working).  The recovery tank’s base gasket is gone (shown in Figure 3 sans gasket), which also eliminated a source of fluid leakage into the base.

No more gasket!

Figure 3. Redesigned recovery tank dock on base.

Finally, Bissell redesigned the sprayer head with better welds and eliminated the extra gaps.  This helps to a degree, but the redesign introduced several new ways for dirty solution to collect in the sprayer/wand connection and stink up the works.  They did nothing to redesign the collection tank tower, which still collects material that leads to ‘Stinky Tank syndrome.’  My current unit had its hose replaced twice, once under warranty.  (This may have been due to my sucking up hot water in order to flush and de-stink the unit.)  The original hose was a little too short and it was under stress when the wand was placed into the clip.  The stress also ended up breaking the clip after the unit was no longer under warranty.  I performed a couple of simple fixes to increase its suction but didn’t implement anything major.  I performed the second hose replacement myself, as I finally found a source for internal parts.  I had to buy a second unit while waiting for the parts to arrive as they were backordered for a month-and-a-half.

 

Why doesn’t it suck (enough)?

The Bissell Little Green’s designers had a challenge, I’m sure…how could they suck up a spill and easily separate the water from the air?  Most wet/dry vacs have a foam filter that the suctioned air passes through, which keeps the water out of the exhaust.  I’m sure the designers didn’t want their customers to deal with replacing a filter (liability lawsuits, you know!), given the tendency for most consumers to screw up the simplest of operations.  This probably led to the current design.

Suction is provided by a motor with a squirrel cage fan attachment located in the base.  Air and water are pulled into the sprayer head, through the hose and into the recovery tank.  The tower-like structure you saw in Figure 2 is divided in half.  The water falls into the tank since it’s heavier than the air, and the air exits the hole in the opposite side of the tower.  The air stream then passes the fan/motor assembly and is blown out the unit’s backside. Simple design, yes, but flawed.  The air has a high degree of moisture in it, and there is no filter of any kind to protect the metal motor and blade assembly.  If you have too much suction the air will have even more water in it; this will accelerate the disintegration of the motor and allow water to blow out of the exhaust port with the air.  You read that right—the motor will disintegrate faster.  This is the Achilles’ heel I mentioned earlier.  When I disassembled my last unit to try and oil the motor, I discovered that the blades and motor casing were so rusty that they practically fell apart in my hands.  That was what caused the motor to scream and whine.  This is a marketing textbook example of built-in obsolescence!  At the time I didn’t know where I could get repair parts, but now I know and will share the source with you.

Making Things Suck More

So, we know that the unit will eventually stop working due to the disintegration of the motor.  Should that stop us from making the unit work a bit better? NO!  If it’s going to have a finite life before we have to repair it, let’s mod it to perform its job better.

O ring to replace is seen vertically in middle of picture.

Figure 4. The Sprayer/Wand junction.

Look at the sprayer/wand connection in Figure 4.  You can see a rubber O ring that attempts to seal the wand/sprayer connection point.  In my last unit this O ring was so loose that no seal was taking place.  I went to the hardware store with the old ring and found a new one that was a little thicker.  Its size is given as a “number 32.”  I replaced this ring, which now requires the user to jockey around a bit when removing/reattaching the sprayer head.  The improvement is well worth the additional effort that will be required.

Now take a close look at the sprayer head/wand.  If you’ll notice, there’s a button that you have to press down on to remove the sprayer.  This is located on a molded plastic lever that flexes when the button is depressed.  This design feature also allows a good deal of suction to exit the hole around the lever.  Additionally, the end of the wand does not seal inside the sprayer head.  This is a second point that allows air to exit around the lever and allows dirty water to accumulate.  Sealing that leak will require a bit more work; however, we can significantly increase the suction by installing a flat rubber seal into the wand below the button/lever assembly.  How much additional suction does that give?  I don’t have a scientific method to gauge it, but by simply holding the sprayer head against my hand with the unit running before and after the mod, it feels as if I’ve approximately doubled the suction.

I took a piece of 1/16” thick sheet rubber and cut a 1.5-inch by 3.5-inch piece from it.  I then applied rubber cement around the edges of the piece (Figure 5) leaving the center dry.

Put glue only on edges of pad, nNOT in center.

Figure 5-a. Apply cement to pad edges on one side only.

 

See? Nothing in the center...

Figure 5-b. The finished pad.

This is important!  If the rubber adheres to the lever, it will be extremely difficult to work the lever and remove the sprayer head.  Next, I folded a piece of paper from a magazine (Figure 6) and inserted it into the slot around the lever.

Protect the lever from glue!

Figure 6. Protecting the lever from glue application.

This allows you to apply contact cement around the lever without accidentally getting glue on the lever itself.  Apply rubber cement to the inside of the wand in approximately the same area where the rubber will go as in Figure 7.

Carefully put glue into the wand...

Figure 7. Apply glue into the wand.

After applying the cement into the wand, quickly pull the paper out of the slot.  Now wait about five minutes to allow the glue to get tacky.  After you’ve waited, flex the rubber piece in an arc as shown in Figure 8 and carefully insert it into the end of the wand with the glue side facing the glue inside the wand.  DO NOT ALLOW THE PIECE TO CONTACT THE GLUE INSIDE THE WAND UNTIL IT’S IN POSITION.  If you do, it will be extremely difficult to remove.  You may want to use forceps or tweezers to assist you in alignment.

Be careful! Pad can stick where you don't want it to go!

Figure 8. Carefully placing the pad into the wand.

Once it’s aligned, press the rubber into place, exerting pressure around the edges of the rubber.  You may have to use a tool to reach in and push the edges down.

Made it!

Figure 9. The pad in it's proper place.

Let the piece sit overnight to dry; then reattach the sprayer head and turn the unit on.  You can hear a little bit of air still exiting the hole around the button.  Hold the sprayer against one hand and cover that hole with your opposite thumb.  If you tried the suction before the mod, you should notice a considerable difference in the amount of suction after the mod.  If you wish to cover the hole with a piece of electrical tape you can easily seal the leak, and remove the tape when you wish to clean the unit.  Alternatively, simply cover the hole with your thumb as I do while using the Little Green.  I am considering milling a second channel around the end of the wand with my Dremel tool, then using a second O-ring to completely seal the connection.  This would allow for more comfortable use of the sprayer wand.

Some tips on using the Green Machine

1)  Clean the unit after each use by holding the sprayer head under warm (not hot! I learned my lesson…) running water.  I will sometimes mix some pine-scented cleaner with water in a bucket and pull that through the hose. Note that you can only suck so much fluid into the recovery tank; there’s a white line on the tank showing the maximum level.  When you’ve finished flushing the sprayer head and hose in this manner, hold the sprayer head above the unit pointing upward for a moment or two to allow all the remaining water in the hose to be sucked into the recovery tank.

2)  Stopping the dribbles. When you’ve finished cleaning a spot and you’ve turned the power off, hold the sprayer head above the unit pointing upward and depress the trigger. Hold the trigger in for a count of five before releasing it.  MAKE SURE THE POWER IS OFF BEFORE DOING THIS OR YOU’LL SPRAY HOT CLEANING SOLUTION ON YOURSELF OR SOMEONE ELSE. Performing this maneuver allows any cleaning fluid still in the hose/sprayer head to drain back into the unit, and prevents leakage when you’re moving the sprayer head around to clip it onto the unit.

3) Clean the recovery tank after each use. Do not allow material to stay in the recovery tank!  This allows the material to soil the plastic and contributes to ‘Stinky Tank syndrome.’  Dump the recovered material into the toilet and flush it. Use the toilet because any pet hair in the water may clog your sink drain.  Run hot water into the tank from the top hole, then turn and twist the tank to thoroughly swish the water around before emptying the tank again into the toilet.  Remove the rubber gasket from the bottom of the tank and clean it with soap and water or pine-scented cleaner as well.  Material tends to collect on the backside of that gasket and also creates a smell.  If you have a bucket that’s big enough, you can dump the entire tank into a water/pine cleaner mix and get things smelling a bit better.

4)  Use only distilled water in the unit. I cannot stress this enough.  The minerals in tap water can build up after awhile and collect in the heater assembly.  This can clog the sprayer when bits of the accumulated minerals fracture off and mix with the cleaning solution. When the sprayer wand gets clogged you’ll see that fluid has entered the head but nothing exits when you press the trigger.   To remove the clog you can usually insert a cotton swab into the channel inside the sprayer head, and gently move it around to catch and remove the clog.  Occasionally the clog gets wedged into the sprayer hole; this requires pushing a slightly-bent straight pin into the hole from the outside to push the clog out. You can then use the cotton swab to remove it.

The heater itself can be cleaned by first disassembling the unit and then removing the cover on the heater but it’s a major hassle.  The heater box sits atop some plumbing bits and has a thin hose entering and exiting on its sides. To get inside it you remove the screws that hold the top cover on.  You’ll see maze-like channels inside the heater, and should see whitish material inside those channels.  Those are the mineral deposits, and you remove them by scraping them out.  You’ll then replace the top cover and reassemble the base.  This can take up to an hour the first time you do it.

 

Getting Repair Parts

I don’t know why it took so long for me to find a parts dealer (despite Google), but Hesco Sales (www.hescoinc.com) will sell you any part they can get from Bissell. There’s a section on their website where you enter your unit’s model number and can pull up exploded diagrams of the unit to help identify your part. In my case the part data wasn’t available on their site. Several emails later they had the part information and made the part orderable. Note that they have a $25.00 minimum order, so my advice is to get a couple of the hose clips I mentioned earlier. They’re inexpensive and make good filler material for your order. Besides, you’ll eventually need them.

Hopefully you found this information useful, and maybe you will be able to save your unit from the trash heap (or have gotten the courage to rescue one from the thrift store).  If one person can keep their unit running longer I’ve done my job.

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January 28, 2010 · 8:54 pm

An X10 Tip—Delaying a Trigger Signal to a Powerflash Module

I recently upgraded my home theater to bring it current with high-def content.  My 12 year-old 50” standard-def rear-projection set was replaced by a 60” plasma display, and my non-HDMI capable A/V receiver was dumped in favor of an Onkyo 7.1-channel preamp/processor.  (Naturally, the 9.2-channel version with Internet streaming audio came out a month later.)  This gave me an opportunity to finally install the separate power amps I purchased as surplus from my employer several years ago.

After opening the pre/pro and perusing the manual I realized I’d need a method of controlling the amps.  The Crest Audio Vs-450s have mechanical power switches and no trigger inputs.  The Onkyo has three trigger voltage outputs that are programmable as to when they turn on.  I needed some sort of interface between the pre/pro in my living room and the amps, which I located in a basement equipment rack.  Basement installation was necessary because the amps have big cooling fans in their front panels.  I went to the web and shopped around for trigger voltage-controlled power strips.  Several companies make them, and they’re pricey (around $200 for a two-outlet unit).  That was out of the question.

I then considered building my own trigger-controlled outlets.  I found several schematics and blog posts from people who’d built their own, but I really didn’t want to tackle yet another project.  Then inspiration hit me—I use X10 for home control, so why not use it to control the amps?  I ordered three Powerflash modules and five X10 appliance switches, and sketched out how everything would connect.  The X10 Powerflash modules have two screw terminals for an input, and can take either a control voltage or a simple switch closure (selectable by a switch on the module).  The voltage input would come from an Onkyo trigger output.  The module has three possible modes of operation; one mode will send an X10 ‘on’ command when voltage is first applied and an ‘off’ command when the voltage is dropped.  Each amp would be plugged into an appliance module and be set to a unique address that matched one of the Powerflash interfaces.  I could theoretically turn amps on and off when needed depending on the listening mode.  For example, if I wished to listen to 2-channel music I could turn on only the front left – front right amp.  When I switch to a movie surround mode other amps would come on.  This would allow a degree of ‘green’ operation and save some money on the power bill.  It was the perfect solution (or so I thought)!

I wired everything together and turned the system on for the first time, but the amps didn’t power up.  I could turn them on with a wired mini-controller but the Powerflash modules didn’t seem to work.  After a bit I had a forehead-slapping moment.  My DirecTV DVR is connected to a UPS in the equipment rack, and UPSes are notorious X10 signal eaters.  I dug out a filter specifically designed for signal-interfering devices and plugged the UPS into it.  No change—the Powerflash modules still didn’t work.  Then I realized that the APC  home theater power bar I’d installed would also filter out X10 signals.  To get around this I ran wires from the Onkyo trigger outputs through the wall and down into the basement.  I mounted an unfiltered power strip on a floor joist below the living room and plugged the Powerflash modules into it.  The power strip was then plugged into a basement AC outlet on a separate breaker from the entertainment system (but on the same phase in the breaker box).  Success!  The amps would then turn on with the pre/pro.

I spent some time listening to the new system and was very pleased with what I heard.  Even without calibration it sounded fantastic.  I was ecstatic!  Then I turned the system off and went downstairs for something, and that’s when I discovered that the amps hadn’t turned off.  After several hours of testing I again found that the amps would turn off with the mini-controller in the living room, so I used that as a stopgap measure while I thought the problem through.  Several days later I realized what the problem was.  The amps would turn on okay because I had the Onkyo programmed with a 1-second delay between triggers.  For example, on power-up the first trigger voltage was activated.  A second later the second trigger activated, and the third trigger finally activated two seconds after the first.  This gave each module’s signal a chance to transmit.  When the power is shut off, however, all the trigger voltages go off at once.  All three Powerflash modules send their X10 commands at the same time and they collide; consequently the appliance modules never get their signals and the amps stay on.  There’s no way to adjust for this condition in the Onkyo.  It was time for more head-scratching.  How could I delay the trigger voltages just long enough to ensure there would be no collisions?

The idea proved to be fairly simple.

X-10 Trigger Voltage Delay Circuit

Figure 1. X-10 Trigger Voltage Delay Circuit

The circuit I constructed consists of just two components, a blocking diode and an electrolytic capacitor.  The capacitor, once charged by the trigger voltage, will retain that charge for a short time after voltage is removed before dropping it.  This should be long enough for a non-delayed Powerflash to transmit its signal and avoid a data collision.  The blocking diode prevents the capacitor’s voltage from bleeding back into the Onkyo’s trigger voltage output.  Any other delayed Powerflash modules would have a different value capacitor to ensure the other  modules transmitted first.  I determined the capacitor value by trial and error.  As it turns out, a 2200 uF, 25 volt capacitor will hold its voltage in this application approximately 22 seconds.  A 220 uF cap holds its voltage for just over two seconds.  So to calculate the time delay, multiply the delay time period (in seconds) by 100, then round up or down to a standard capacitor value (in microfarads).  I built my delay circuit on a small piece of perfboard and used two mini screw terminal blocks to connect the input and output wires.  I protected the entire assembly from shorts by placing a piece of heatshrink tubing over it.

If you do any work with X10 devices, especially Powerflash modules, this little circuit could come in handy.

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