Re: Is my Tek 468 beyond repair?


tgerbic
 

Thought I would pull out my 468 and see if I could find anything useful to post. Well no trace on power up :( However it passes self test. Had to replace the 1200uf cap in the power supply to bring it back to life. First repair on this scope since new. Will probably replace all the big PS filter caps in the future in this and my 465B scopes, since I bought them from Tek in the 80s and they use the same parts. Cheap insurance, maybe... The 465B has never been touched. Guess I should go fire that one up too. They have been sitting for a decade.

Self test runs with 8's and dots first then a bunch of zeros flashing around on the display, then it goes blank when the test passes.

I did a quick once around the processor to provide some general signals for a running unit.
1 5Mhz Squarewave
2 5Mhz Squarewave, half size from 5V down to ~2.5V
3 Low, short high pulse on power up
4, 5, 6 Low
7 500Hz digital signal with 2ms positive pulse
8, 9 High
10 100Hz digital signal with 10ms positive pulse
11 High, occasional negative pulse
12 to 19,k and 21 to 33 Address/data/control constant traffic
20 Gnd
34, 35, 36 High
37 132Hz squarewave
38, 39 High
40 +5V VCC

Regards
Tony

Join TekScopes@groups.io to automatically receive all group messages.