Questions about tubes and gear that glows. FAQ
In Reply to: schematics posted by tunenut on October 2, 2020 at 17:01:09:
You mentioned initial LED problem, I would first check the PS voltages. It is a separate LED supply which comes from the digital 5 volt supply. All you need to do it is a voltmeter. The supplies are separate enough that it is probably a low voltage only problem. If you want to give it a try, take the cover off and take pictures and post them.
If you want a guess, it would be bad filter cap in the digital 5 volt supply. My guesses are usually wrong, but so many times, problems are immediately visible by just taking off the covers. Look for a bulging capacitor in the PS section, particularly ones that show on them voltage ratings less than 100 volts.
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Topic - Audio research preamp broken - tunenut 17:40:48 09/28/20 (13)
- RE: Audio research preamp broken - fredtr 10:59:49 09/30/20 (4)
- schematics - tunenut 17:01:09 10/02/20 (3)
- RE: Audio research preamp broken - bouncy ball 08:08:27 09/30/20 (0)
- Thanks all- some comments... - tunenut 15:52:32 09/29/20 (3)
- RE: Thanks all- some comments... - airtime 07:32:30 09/30/20 (2)
- RE: Audio research preamp broken - airtime 13:20:04 09/29/20 (0)
- RE: Audio research preamp broken - Chip647 20:00:41 09/28/20 (1)
- That happened to me with an SP-9 years ago - E-Stat 09:13:34 09/29/20 (0)
- RE: schematics - fredtr 17:37:51 10/02/20 (0)