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Hoffman Amps Forum image Author Topic: 6G16 Mojo Build - Ground Switch Question  (Read 1882 times)

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Offline waldner

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6G16 Mojo Build - Ground Switch Question
« on: July 01, 2021, 02:23:00 pm »
I'm pretty far along on a 63 Vibroverb Mojo kit build. My question is regarding the .047uF cap connected to the ground switch (see attached pics).  I was hoping to use this , I thought, unnecessary ground switch as a negative feedback switch.  Can I eliminate the cap and just leave the tube socket's pin 8 connections grounded to the chassis screw only.


Also any other tips or advice are welcome.  I have never wired the front of a fender style chassis before that is angled and tight like this with so many pots.  What do you guys do to make soldering go smoothly? 


Thanks!





Offline sluckey

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Re: 6G16 Mojo Build - Ground Switch Question
« Reply #1 on: July 01, 2021, 04:41:05 pm »
Can I eliminate the cap and just leave the tube socket's pin 8 connections grounded to the chassis screw only.
yes
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Willabe

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Re: 6G16 Mojo Build - Ground Switch Question
« Reply #2 on: July 01, 2021, 04:44:53 pm »
You can put the pots in the chassis from the outside, backwards left to right, and wire up anything that's on the pots, then put the pots in correctly and solder up the wires from the eyelet board to the pots. 

Offline Medley

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Re: 6G16 Mojo Build - Ground Switch Question
« Reply #3 on: July 10, 2021, 05:51:41 pm »
I'm pretty far along on a 63 Vibroverb Mojo kit build. My question is regarding the .047uF cap connected to the ground switch (see attached pics).  I was hoping to use this , I thought, unnecessary ground switch as a negative feedback switch.  Can I eliminate the cap and just leave the tube socket's pin 8 connections grounded to the chassis screw only.


Also any other tips or advice are welcome.  I have never wired the front of a fender style chassis before that is angled and tight like this with so many pots.  What do you guys do to make soldering go smoothly? 


Thanks!
I just finished a Mojotone 6G16 a couple months ago, and when it came to that .047 cap attached to the ground switch in the layout, I didn't even install it because as far as I could tell, it was just there for looks. The one end is soldered to the ground from pin 8, the other end is soldered to one of the lugs on the ground switch. However the ground switch is completed isolated from the chassis, so it appears to me it does absolutely nothing. I've thought I might install it between the hot side of the standby switch and ground to serve as a "pop" capacitor but haven't done so yet because I don't actually use the ground switch. My 5F4 build does have such a cap installed, per both the schematic and the layout diagram, FWIW.

 


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