Sound Technology 1500A Tape Recorder Test System Part II

This guy has been interesting. A computer of sorts from 1980. Removed all the boards and started replacing tantalum capacitors one by one. Once the big values were replaced each board came to life and finally the screen came on. The voltages also were correct.  Next step is calibration and try to pass the self test..

Sound Technologies ST1500A - Tape and LP Test System

Chris and have been working on this guy off and on for a while. There is finally light at the end of the tunnel.  Here is a pic of the ancient guts.

 With these boards removed we get all the correct voltages. Not so much when they are installed. I started replacing all the orange tantalum caps... Lots of caps.

 

This is what the input board does to the 1500A. Very sad. 

 Fortunately with the input board removed there are some signs of life.

 Can't belive how happy I was to see this boot up screen.. LOL.... Now back to replacing all the tantalum caps on that dam input board and hope it works.

Sound Technology Distortion Analyzer and Stereo Test Panel

Sound Technology1200A Stereo Test Panel and 1700B Distortion Measurement System. My friend Chris dropped these by yesterday. It looks like I have to stretch my grey matter more to learn to use these. Joke is on him as he has to teach me to use them lol...