Flaky Mid Scoop switch

Alonzo · 4015

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Offline Alonzo

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on: February 29, 2016, 08:04:41 PM
Seems I've developed a flaky Mid Scoop switch, Tode now hums until I touch the plate anywhere near the switch or press on the switch shaft.  I've inspected and retouched the joints but the hum remains (increases and decreases with volume increase/decrease).   There's no hum in at the "flat" selection but a good amount in Em or Ef.
What's the brand of switch so I can get a replacement?  Thanks!

Alonzo
Gameroom:>Mainline to HD820, SR45 to Pipette
>BeePree Kaiju & SII to Altec 19 knockoffs
Office:>BH Stat amp to Koss 95x, T20 SET to JBL 4309s
Den:> MorePlay 845 SET to Altec Valencia's


Offline Doc B.

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Reply #1 on: March 01, 2016, 05:18:41 AM
You can get one from us or you might be able to install the Goldpoint equivalent, though I'm not sure how easily the parts would connect to it vs. the stock switch. However I wonder if it is the dress or connections of the components attached to the switch that are picking up the hum rather than the switch contacts being an issue, since you are only getting the noise when those components are switched into the circuit.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline Alonzo

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Reply #2 on: March 01, 2016, 06:32:07 AM
On the initial build I had hum and scratchy sounds but they were solved by new pickups and getting a good clean and service on my guitar.  It has been playing fine (an hour +/- per week) for many months.  I thought it might be a bad ground somewhere and wanted to have a new switch on hand once I have it open if I can't find an obvious culprit.  I'll walk the circuit and touch up the solder, if no change then I'll email for a new switch.
Thanks,
Alonzo

Alonzo
Gameroom:>Mainline to HD820, SR45 to Pipette
>BeePree Kaiju & SII to Altec 19 knockoffs
Office:>BH Stat amp to Koss 95x, T20 SET to JBL 4309s
Den:> MorePlay 845 SET to Altec Valencia's


Offline Doc B.

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Reply #3 on: March 01, 2016, 08:53:37 AM
Yup, the 10 Megohm input impedance and the gain of the EF86 are a little ruthless in exposing noisy pups, pots and switches in a guitar, particularly if the amp is run with no negative feedback on the clean/crunchy control. Good grounding in the AC mains wiring is important too. At work my Tode is very quiet with a guitar plugged in. At home where my safety ground is pretty old I get hum from my guitars when plugged in. Time for a new ground rod this spring.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.