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Harris SX Series parts?

Search Newark, Mouser, DigiKey and other sites for parts. I did that for the blue filter caps. Some components such as the original MOSFETs, TIL-308 display chips and others are no longer produced by the oiginal manufacturer. Harris can't sell that which they cannot buy. A wise investment is to buy a few of the U42/U46 chips on the S&M board. These are not in the spare parts kit.
 
Yes, I had an SX-1 that had a +5 volt supply failure that cascaded into other supply/component failures. The big blue power supply capacitors that everyone mentioned are fed via some fine wires going through some wonderful ribbon cables and some hair-fine traces on an interface PC board in the bottom of the transmitter. The overall effect is that the big blue capacitors have enough instantaneous current to fry everything in their path. The fuses were on the WRONG end of the wiring... they were not on the output of the caps, so when the devices that caused the short did their deed (I think there were some tantalums on the CPU module), followed by the wonderful fuses, the ribbon cables became the fuses.

Once I got all of the power supplies to work, I finally had to diagnose the SX-1 we had dead because the EPROM chips were gone and the CPU wouldn't run the firmware, no matter what we tried - we had replaced EVERY IC on the modules we could, except these. Harris didn't have them or a way to make them anymore. The tech said they just threw away the equipment to make new chips last month (that was two years ago)... So if you have a set of working EPROM's and a EPROM burner that can copy them, you should make yourself a fresh set (and maybe a set for me? ;D

Everything else is a standard 7400 series logic gate, mostly, so repairing them is fairly easy.

I also had the devilish idea to build a controller module for this transmitter. It was a shame it had to die because of one silly thing not being available, and it took 3 continuous days work to figure it out - man was I tired!
 
Guys ... I found someone who has extensive knowledge of the SX and is quite fair in his pricing when it comes to resurrecting older SX cards; Oscillator, PA, PDM, etc. He also can retune (either in the field or at his shop) any SX series transmitters.

He's going to rebuild a couple of cards for me in the next week ... his name is Mike Patton down in Baton Rouge. Google search Michael Patton & Associates and his info will be available.

Thanks for ALL of the input on this ... I really DO like the SX series transmitter and when they run they run great, but when they get cranky, they're cranky!
 
Feel your pain on that SX-1! Had the exact same thing happen with mine. Big blue electrolytic shorted to ground and took out a lot of downstream components. And the PROM chips with them. Had to retire her. Replaced her with a new BE AM 1A and back in business.
 
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