|
|
Post by Pinetree on Mar 28, 2020 17:27:41 GMT -5
Working on a HSS guitar for a friend. 1 volume 1 tone. 5 way switch. Triple checked against the schematic. Everything works, except the output is easily half what it should be.
I've checked everything. Re-soldered everything, replaced the wire to the jack with some shielded cable, cleaned the jack, bent the lugs so they're tight, and I'm completely stumped.
What am I missing here?
|
|
|
|
Post by Leftee on Mar 28, 2020 18:59:23 GMT -5
Does the volume pot check out ok?
|
|
|
|
Post by Peegoo 🏁 on Mar 28, 2020 21:06:42 GMT -5
You have a clip test lead? Unground all the pickups to isolate them from the circuit, and test each one direct to the amp. If they all check out, unground the pots and check them individually for spec. If they are ok, check the switch.
But before you do that, does the guitar have the black shielding paint? If so, chances are good one of the solder tabs (switch, pots, jack) that carries signal is touching the shielding. This black paint will sometimes not create a dead short, but a resistive short--and that makes it act like a voltage divider (the resistive track on a pot), causing the volume drop.
|
|
|
|
Post by Pinetree on Mar 29, 2020 13:46:19 GMT -5
Well I honestly thought the old black tape around the output jack trick was going to do it, but it did not.
However, while screwing around I had a brief burst of noise that led me to believe that the output jack was no good. I don't think I've ever actually seen one go bad before, and I had cleaned it with DeOxit and a .30 cal brass brush... but the barrel part had come loose from the crimp and was spinning inside, so I replaced it with a Switchcraft and all is good.
Thanks.
|
|
|
|
Post by Peegoo 🏁 on Mar 29, 2020 14:05:38 GMT -5
Very cool! Good find!
|
|
|
|
Post by Pinetree on Apr 2, 2020 12:23:46 GMT -5
Well, hell. Plugged it in again today and this thing's obviously got an intermittent short.
|
|
|
|
Post by Peegoo 🏁 on Apr 2, 2020 14:51:29 GMT -5
You mentioned you reflowed all solder joints. Hit each joint with a flux pen and reheat one by one. If that doesn't solve the issue, and there's no short to shielding paint or foil, suspect the volume pot(s) as being the culprit (internal fault). If these don't pan out as the cause, take some time with a meter and test between signal and ground in multiple places in the circuit to determine if the issue is an intermittent short (closed circuit) or intermittent open.
|
|
|
|
Post by Pinetree on Apr 2, 2020 15:09:10 GMT -5
Got some new pots in the mail today, and replacing the volume did the trick.
Thanks brother, this one was a real head-scratcher. A multitude of elements conspired against me, but I prevailed.
For now.
|
|
|
|
Post by Pinetree on Apr 2, 2020 17:56:24 GMT -5
|
|
|
|
Post by Peegoo 🏁 on Apr 3, 2020 22:46:38 GMT -5
The tone pot looks like it's missing the center solder tab. Is that just the angle of the camera causing that?
|
|
|
|
Post by Pinetree on Apr 4, 2020 1:55:51 GMT -5
The camera is pointed straight down, it's there.
Everything is working fine, thanks again.
|
|
|
|
Post by LTB on Apr 4, 2020 8:35:16 GMT -5
I guess it is not a "have to" thing but did you go back and remove the rosin off the pots etc? Just a looks thing |
|
|
|
Post by Pinetree on Apr 4, 2020 9:21:53 GMT -5
Not usually.
|
|
|
|
Post by Pinetree on Apr 7, 2020 16:33:20 GMT -5
Owner is happy.
It's off my bench and outta my house so I'm happy.
Win/Win
|
|
|
|
Post by funkykikuchiyo on Apr 7, 2020 17:12:53 GMT -5
Every so often, the best you can say about a repair job is "it went away"!
|
|
|
|
Post by Peegoo 🏁 on Apr 7, 2020 19:30:55 GMT -5
"...and the owner is happy."
|
|
