Advice needed. Terminal 46 over limit for resistance check.

CuriousMister · 17623

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Offline CuriousMister

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Reply #15 on: December 20, 2023, 03:15:14 PM
You’re right about the 130ohm resistors.  Only one could be read while attached - the only good one.  3 are toast.  Based on what’s online, does it matter what wattage rating I replace them with?  This may have been my problem from the beginning.  I’ll replace them and report back when installed.

I really do appreciate your advice.



Offline Paul Birkeland

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Reply #16 on: December 21, 2023, 05:36:52 AM
That issue will happen either from the 2A3 insertion as I mentioned, or from backwards 100uF/450V caps, which act like a short when installed backwards and destroy the 130 ohm resistors.

If you use 1/2W resistors, they will probably last a few days/maybe a week.  A 1W resistor around a year or two maybe, and a 2W resistor indefinitely (other than failure from fault conditions of course).

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline CuriousMister

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Reply #17 on: December 28, 2023, 03:30:14 PM
Another request for advice after installing three new 130ohm resistors.  The good news, my initial problem is fixed.  I think.  A new one sprung up though.  At both terminals 4 and 17 I get fluctuating DC readings (trending up over time).  Measurements ranged from 8 to low 30s after a second reading.  29 is also not zero.  It is -1.  Do you have any ideas or thoughts? 

Once again, thank you for helping me get this one over the finish line!

Tom



Offline Paul Birkeland

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Reply #18 on: December 30, 2023, 06:15:12 AM
Another request for advice after installing three new 130ohm resistors.  The good news, my initial problem is fixed.  I think.  A new one sprung up though.  At both terminals 4 and 17 I get fluctuating DC readings (trending up over time).  Measurements ranged from 8 to low 30s after a second reading. 
What are the units on this reading?  Is that 8 to 30 mV, 8 to 30V, etc?
29 is also not zero.  It is -1.  Do you have any ideas or thoughts? 
29 connects to all sorts of terminals via the buss of black ground wires.  If it doesn't measure exactly the same as any of the terminals its wired to, then there's a bad solder joint along that string of black wires.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline CuriousMister

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Reply #19 on: December 30, 2023, 12:04:57 PM
The readings at 4 and 17 were both in mV.  I’ll do some joint management on the black wires connected to 29 like you suggested later tonight.



Offline Paul Birkeland

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Reply #20 on: December 30, 2023, 01:04:48 PM
0.004-0.017V is close enough to 0V to not worry about in that spot.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline CuriousMister

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Reply #21 on: December 30, 2023, 03:26:49 PM
I think we are golden! I measured all the terminals connected to 29 by black wires. They are all effectively the same - between 0.7-1mV. Would you say I’m ready to move on to the hum test now?  SO thankful for your trouble shooting.



Offline Paul Birkeland

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Reply #22 on: December 31, 2023, 06:24:06 AM
Sure, that seems reasonable.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man