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gain control/standby switch


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I found very simple instructions for a standby switch, take one red wire from the PT(what

is this, power transformer??) and connect it to one end of the switch and the other end of

the switch to where the red wire would originally go. is this correct. Also i was wondering if

a gain control would do the same job as an attenuator. If so i have heard to put it on R7 so

do you take the cap off of R7 and connect one end of R7 to one side tab of the pot and the other

outside tab to the other end of R7? Also which works better a 500K or 1 Meg pot.


Another thing, when working in the amp do you only check voltages on the cap your working

on or all the ones around them? if you bump one next to it will it shock you.

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Yep.. power transformer.. and that's the right instructions.


No a gain control wont do the same job as an attenuator.

What happens is you get less preamp drive, so when you crank it down and the volume up, you're getting power tube overdrive..

of if you crank the gain up, you get more of the preamp tube sound.


Either pot value will work fine.. it just depends on what you like after you get it in.

I was just cleaning up my papers, so I don't know what I've got in mine.. I think it's a 500K in one head and 1M in the other.



a Master volume didn't do enough for me to justify it being there, either.


And no that's the wrong way to wire a gain pot, too. You have to connect one end to the wiper, after all the wiper lug, middle lug, sets the range. Bitmo Spanky uses a 500K by the way.



You don't really have to worry about bumping a cap at all, unless you bump where it's connected and the voltage can go through, or unless you bump it so hard you break a solder connection.


Just bleed the big ones. And I didn't always do that if I wasn't going to be anywhere near there.

And some, like C1 C2, just replace whenever you want, they never have a charge in them in my experience. I don't think they even hold a charge, in fact.



I decided to put a 6v6 tube in my other head, so I'm not looking for another amp right now*

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Think about it! Actually, C1 and C2 bleed off through the plate resistors in series with the rail resistors in series with R11 to ground. And I've never gotten bitten by a C3 or C4 cathode cap, except when the amp was on and it had power to it. Even with only 1.5v on 'em, they can bite hard enough to make you subconsciously skittish for a month. But if you check for voltage at any exposed lead of any rail resistor and find less than 200mV, the amp is safe enough for little children to play with. Just be sure to unplug it first. Don't want 'em flipping the switch OR chewing on the cables, ya know. :)



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Thanks for the info everyone. I was wondering then what the correct way to wire this

gain pot is. Just in case i decide to do this. I really think i will just do a bitmo spanky and

standby switch. I got to use it tonight at normal volume(tired of bedroom super low levels).

I loved the sound sooo much so i think just doing a spanky will get me that tone only a

little better without changing the natural character of the amp too much. I used it where

the volume control was to my eyes at about 10:00. I loved this tone as it just barely started

to crunch when i would strum really hard. I'm getting ready to place an order at MF with

a 20% off coupon they sent me to get a clean boost and i was wondering what tubes to

buy or if the ones in a V3 are good. If the ones in a V3 are decent would it be a good idea

to put new ones in the V3 head and put the V3 stubes in my V2 combo.

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