This is a Heathkit HW-101 I picked up at an estate sale. I washed the internals, serviced all tube sockets, checked / replaced tubes, made repairs to an intermittent preselector (was never soldered to the board!!), changed a few out of spec resistors, installed new feet, cleaned and lubricated the VFO, and aligned it. Pretty darn good looking 50 year old radio!
This is a Super Star SS-3000HP CB radio a friend picked up and wanted me to repair. Boy, this thing had wires cut, parts missing, exposed digital display, no deviation on FM transmit, no recieve audio, and was a mile out of alignment. How do things get this bad? Here's a couple of vids and some pics...
This is a HP141T mainframe, with a 8554B spectrum analyzer and 8552 I.F. plug-ins. These were about $7000 in 1972 dollars, waayyyy beyond any toy I could have afforded in those days!! It's amazing, 50+ years later, thee things still perform pretty well.
I got this from a friend in the Rockingham area. I did the typical recapping, changing some out of spec resistors and such, cleaning, lubricating various controls, etc. After bringing it up on a variac, the fuses in the 8552 I.F. module kept blowing. Digging into the schematics, I found a crowbar was tripping, due to over voltage from the 141T display unit.
In the 141T, there's a neon Z82R7 lamp with a drop of Krypton 85 that sets the firing voltage at 82 vdc. Yep, radioactive parts... It has a 10 year half-life, and was now firing upwards of 100v, causing the crowbar to crow and blow fuses :-) . I strung a few zeners in series to give me about 82v, and replaced the Krypton thing with more modern tech. All is now well, and this 50+ year old spectrum analyzer is working like new.
Once upon a time, there was a junked out HP-564 Storage Oscilloscope...in my salvage yard :-) Once the crème de la crème, it now sat, dirty, broken, and forgotten. It had an open hv transformer winding, problems in the timebase module, missing the screen graticule, bad tubes, etc.
I had a junker RCA WO-78 scope, had picked up flea market HP input and timing modules for that mainframe, and had a junk HP-561 mainframe. It was time...
I was able to hack the old WO-78 HV transformer in, used the 561 graticule to fix the crt face, used parts from the spare modules to repair the originals, and the 561 had the needed mainframe parts. A few new tubes, a fresh calibration, and the 564 was back to its former glory. I love boatanchors!!
