Seductor resistance help

Reptiled · 3937

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Offline Reptiled

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on: January 26, 2018, 08:33:23 PM
Just finished wiring one of my Seductors. I'm checking the resistance using 9U as ground. I am getting 0 Ohms at 18 and at 28 the meter goes from 5k, 10k, 22k till finally OL or open. I have checked the wiring over and do not see any bad solder joints or misplaced connections. Is it possible that I have a bad transistor?


Thanks,
Dan



Offline Paul Birkeland

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Reply #1 on: January 27, 2018, 04:51:09 AM
These resistances don't depend on a transistor.

Do the twisted leads of the two 220 Ohm resistors that connect to 18 happen to touch the shield of the twisted pair of wires underneath them?

I wouldn't turn on the amp until terminal 18 is reading properly.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Reptiled

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Reply #2 on: January 27, 2018, 05:51:06 AM
Thank you for your reply.

They do not. Checked solder and connections again. Here are some pictures of the connections. Maybe something obvious?



Offline Paul Birkeland

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Reply #3 on: January 27, 2018, 06:04:03 AM
Can you temporarily remove the twisted pair of leads from the 220 Ohm resistors from terminal 18, then recheck its resistance?

Also, 18 and 28 connect together with a piece of wire.  They should have very similar resistances.  If they don't, the wire isn't connecting them (poorly soldered, connected to the wrong terminals, or broken).

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Reptiled

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Reply #4 on: January 27, 2018, 06:21:59 AM
I removed the twisted pair 220 Ohm from 18 and still get 0. There is continuity between 18 and 28. I resoldered my connections on 28 and 18. The white wire that connects 18 to 28 is fine.
Could painting the top of the plate have anything to do with this?
« Last Edit: January 27, 2018, 06:33:06 AM by Reptiled »



Offline Paul Birkeland

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Reply #5 on: January 27, 2018, 06:34:18 AM
Try remeasuring the resistance at 28.


Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Reptiled

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Reply #6 on: January 27, 2018, 06:51:34 AM
At 28 I get 0.3 Ohms or 0.00k Ohms??? Very puzzling to me. There is not a lot going on here.
FYI: I do have another Seductor to wire so I have parts to troubleshoot with if that helps at all.
« Last Edit: January 27, 2018, 07:35:38 AM by Reptiled »



Offline Paul Birkeland

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Reply #7 on: January 27, 2018, 07:56:51 AM
How about the resistance at terminal 12?  12 and 28 are the same test point, just one for each channel.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Reptiled

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Reply #8 on: January 27, 2018, 07:59:25 AM
Yes, 12 is good. I am wiring this for mono, does this matter?



Offline Paul Birkeland

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Reply #9 on: January 28, 2018, 07:24:36 AM
Stuff like this can throw off your resistances too.  I'd go through and trim up any other leads that are poking around where they shouldn't be.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Reptiled

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Reply #10 on: January 28, 2018, 09:32:31 AM
Unfortunately ( or fortunately ) it's pretty clean in there, That was the leg of the transistor in the picture.
« Last Edit: January 28, 2018, 10:18:50 AM by Reptiled »



Offline Reptiled

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Reply #11 on: January 28, 2018, 10:17:12 AM
I've just re-soldered 25-32 and then 17 and 18. Still nothing. There is resistance but still not even near 8k. I'm at a loss here. I think I'll start on the other seductor and see what I get with it.