Hi: I recently acquired a Tek 475 in what seems to be fairly good shape for its age. It does have some minor problems that I'd like to take care of and I am wondering if there is a website/discussion forum that could address some of the following (or if somebody would want to respond here, that would be great too!):
- Noisey controls and switches - I plan on carefully cleaning with contact cleaner (isopropel-based, no lubricant), lube shafts where necessary.
- 2 MHZ wave forms are out of focus when the 100 MHZ and 200 MHZ bands are selected, it is sharp in the 20 MHZ BW. - Suggestions?
- Some floating of waveform when observing a trace for a period of time
- e.g. 2-3 mins.
- Significant wave form bounce when switching from DC - gnd- back to DC....the waveform reappears above or below the DC baseline with a bias of approximately 10-20% of the voltage scale - but not on all scales.
- Recal the scope.
I have a service manual. Any tips/pointers/suggestions as well as known 'weak' spots that I should investigate are welcome. Thanks John