Just bought some MPQ6700s to repair a Crest CA9. I had it working, then I inserted the driver board in backwards. For those who aren't aware, a CA9 has +/- 120V rails. It vaporized the feedback trace (fixable, but time consuming since all the output devices have to get re-mounted on the heatsink), but miraculously the output module tested good once the trace was repaired. Destroyed almost every transistor on the driver board though.
This is one of those mistakes you only make once, then you label your extender cable.
This is one of those mistakes you only make once, then you label your extender cable.
Bought a couple of knickknacks for this ridiculous car audio project, which has taken a couple of sharp left turns since its inception - each more expensive of course. 
Since the new system will be mostly autonomous from the original head unit, and since I still want to listen to NPR from time to time, I needed a way to inject the factory radio audio back into the Big Amplifier I've chosen, which has only digital inputs! (How very 21st-century.) So ordered a little $13 stereo-RCA-to-S/PDIF ADC box for that, along with a couple of sundries like a dashboard CD-slot-mount tablet holder bracket thingy and a "Flirc" USB IR receiver.
This is gonna be pretty cool if it all works, heh.
Since the new system will be mostly autonomous from the original head unit, and since I still want to listen to NPR from time to time, I needed a way to inject the factory radio audio back into the Big Amplifier I've chosen, which has only digital inputs! (How very 21st-century.) So ordered a little $13 stereo-RCA-to-S/PDIF ADC box for that, along with a couple of sundries like a dashboard CD-slot-mount tablet holder bracket thingy and a "Flirc" USB IR receiver.
This is gonna be pretty cool if it all works, heh.
Took a bit of a risk, looking for a used laptop for either myself or my daughter to use. I bought a non-working one for $60. I was prepared for some hard work, found some YT videos on checking and replacing PS MOSFET's in it. Did a quick check tonight just so I could order parts ASAP for it, and it looks like just a bad brick! Fingers crossed...
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Joined 2009
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This one has been a bit of frustration. It took over 8 months, countless emails, threats to start a claim with Paypal, and a few other tactics to get my order shipped.
These synthesizer modules are notorious for poor documentation, but this one had an 8 page build manual which I downloaded when I placed the order. There was no BOM, just the typical list of reference designators and values. Assuming I would have my board in less than a week since it was "in stock" in Boston, I put together a build box with all the parts.
I knew as soon as i saw the board that all of my resistors and some of the caps would not fit, so I ordered the right stuff from Digikey, who offered "$10.95 2 day shipping" which I chose. I got my order in on time so it should have shipped yesterday morning, but as of 5 minutes ago Fedex doesn't have it yet.
I decided to sit down with the build box and sling some solder this morning. Unfortunately there were still a few surprises left. What happens to a box full of parts left unattended for 8 months? I don't know how, but it seems that some of the parts sneak out of the box and into something else. Complete inventory check is in progress.
I didn't realize it until today but the 15 mm pots that were still in the build box will not fit. The board is laid out for 12 mm pots which are not common, so the experiment that is currently underway is "make 9 mm pots fit." Its too soon to know how that will work out, but it does look like this will not be a quick build.
After a sleepless night of Googling, configuring & cussing (getting too old for these), it looks like the little Win10 mini-PC is going to work great in the car. It'll have a wireless display of artist folders & playlists via Android tablet clipped to the dash, but a small key-mapped IR remote with real buttons for all control input. I find it's much easier to keep eyes on the road with this combination instead of trying to push virtual buttons on the tablet's touchscreen, since the remote can be operated by feel.
One really fun feature is wake-on-wireless-LAN, which allows me to sync the music collection in the car from my nice warm living room while it's sitting in the garage! Doesn't get any lazier than this!
Anyway - this morning I splurged a bit and ordered a petite 1TB M.2 2242 SSD to tuck into the little mini-PC. It's working now with an old 2.5" external USB drive for music storage, but that thing's just too slooow, man.
One really fun feature is wake-on-wireless-LAN, which allows me to sync the music collection in the car from my nice warm living room while it's sitting in the garage! Doesn't get any lazier than this!
Anyway - this morning I splurged a bit and ordered a petite 1TB M.2 2242 SSD to tuck into the little mini-PC. It's working now with an old 2.5" external USB drive for music storage, but that thing's just too slooow, man.
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Joined 2009
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Shame on me. I just did it again. Found a helluva deal on Amazon.ca for a new production "Bugera" branded 5U4 (coke bottle). Almost certainly made by Shuguang by the looks of it, which is fine with me. I have had relatively good luck with Chinese tubes in the past.
$14.99 Canuck Bucks and free shipping. How could I not buy it?
It actually looks identical to the "Preferred Series" 5U4G from thetubestore.com (which is indeed made by Shuguang and sells for over $50 CAD plus shipping).
$14.99 Canuck Bucks and free shipping. How could I not buy it?
It actually looks identical to the "Preferred Series" 5U4G from thetubestore.com (which is indeed made by Shuguang and sells for over $50 CAD plus shipping
).
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