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Bottlehead Kits => Crack => Topic started by: Immanence on April 28, 2022, 07:42:05 PM

Title: A few resistance check questions
Post by: Immanence on April 28, 2022, 07:42:05 PM
Hi all,

All of my resistance checks are good except for these:

B3/B6 ready 3.6 rather than 2.9.

7/9 read 2.9... should I be worried about that much deviation?

Also I get a 3m reading from 22. Which worries me, because 22 isn't connected to anything...

Thank you all!
Title: Re: A few resistance check questions
Post by: Immanence on April 29, 2022, 04:17:11 AM
Hmm, I really don't understand the reading at 22. It isn't connected to anything, other than the bolt that secures the PT-10. Does that signal an issue there?
Title: Re: A few resistance check questions
Post by: Paul Birkeland on April 29, 2022, 04:17:50 AM
The bolts on the PT-10 all need to be tight for 22 to come down.

If you wiggle the black wires at the headphone jack, are they both well captured by solder?
Title: Re: A few resistance check questions
Post by: Immanence on April 29, 2022, 04:23:28 AM
Black wires by headphone jack are well secured. Should I try tightening the pt-10 bolts? I'll see if they have any play.
Title: Re: A few resistance check questions
Post by: Paul Birkeland on April 29, 2022, 04:28:10 AM
They aren't tight enough if all those terminals with a bolt passing through don't show 0 ohms.

B3 and B6 wire to 7 and 9, so those resistances shouldn't be different.  It's unlikely for both of those wires to be loose which is why I asked about the black wires at the headphone jack, as that's a common solder joint that doesn't get enough attention, and it could cause a deviation at both terminals. 
Title: Re: A few resistance check questions
Post by: Immanence on April 29, 2022, 04:36:37 AM
22 is good now, thanks!

I'm getting 2.9 at b3/b6/7/9 now as well.

Could tightening the bolts have done that? I also... changed the batteries in my multimeter from last night. (but I wasn't even getting a battery notice?!)

Title: Re: A few resistance check questions
Post by: Paul Birkeland on April 29, 2022, 04:44:25 AM
Tightening the bolts won't change B3/B6/7/9 but moving the amp around could jostle a loose solder joint.  It probably wouldn't hurt to give a little extra heat and solder to all the solder joints where a black wire lands (except for the center post of the 9 pin socket).
Title: Re: A few resistance check questions
Post by: Immanence on April 29, 2022, 06:07:44 AM
Nice, thanks. I'll do that and recheck my resistances.