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Two things.
1. Make sure your switch is clean and provide good contact across all ranges. It is S2 Range switch.
2. I don't think this is it (I think only the lower dual triode is involved for DC, as for everything else), but just in case, have the tubes been checked?
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Tubes and resistors are fine. R22 measures 9k so iam not sure if that could be the issue.
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Switch. Check the switch. Make sure it makes good contacts. Clean if necessary, Deoxit D or any contact cleaner (be careful and don't spray it all around).
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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I cleaned and checked the sw2 switch, its fine. Has to be something in the .5v to 15v circuit. Iam going to check the ac operation.
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No ac function. Pegs the meter to the left, no adjustment.
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If I had it in front of me, I would triy to trace the signal on one of the non-working functions.
Try to trace and highlite at least one non-working path.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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At this point, there is no input, just internal voltages
Which are incorrect and not sure what they should be.
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Those will probably depend on teh switch combination.
Could you list some that you see, their values and what they should be (if you know correct values)?
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Check out this crazy zero pot operation. Touching it drives it crazy. Its rubber tipped. Also the 6al5 has no negative voltage on it.
https://www.dropbox.com/scl/fi/gnvltn9la...fvikk&dl=0
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If this is R22, check the voltage on the wiper (86V).
If this is R33, see if the lower pin indeed connected to GND, the wiper is indeed wipes, and if the pot is OK.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
(This post was last modified: 11-10-2024, 03:29 PM by morzh.)
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I measured the wiper of r22 , 95vdc.
(This post was last modified: 11-10-2024, 05:14 PM by daveone23.)
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The resistor you are touching at the video, is it R22 or R33?
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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R22, but it doesnt do that all the time. Strange. What do you think of the 95 voltage. I guess its close.
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Yes, it is close. It is a solid state diode rectifier, so the voltage won't depend much on the load, as would with tube rectifier.
However the behavior is strange.
Also, see if this pot,s case (and so the shaft) should be grounded through the fron panel, and somehow it is not.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
(This post was last modified: 11-10-2024, 07:20 PM by morzh.)
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Case and shaft go to case. Center wiper of r22 has 3kohms to case.
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