Tonemender really wierd problem, what the heck is wrong? Video inside.

[jimmybjj]

The tonemenders controls were all at zero, i didn't think about it until after i uploaded the video. The only information thats not on the video (at least i think) is the tonemender works in bypass on the champ. Please help i have no clue what to do. I have also tried it trough my other amp, marshall 18 watt, same problem as the champ.

http://www.youtube.com/watch?v=RCD0-EmpHsk

[GibsonGM]

WEIRD. But not very hard.   If it works in bypass, I'd suspect something was mis-wired in the switching...it's 'good enough' to let you turn it on/off, but screwed up enough to not really be 'true bypassing'.

What comes to mind is DC from the LED getting to your output (via a bad switch wiring?).  That is what it sounds like when you've got the Champ hooked up.  Ruby probably has an input cap to block DC, right? The Champ (very nice, BTW!) and the 18W probably doesn't, so you can hear it. That, my friend, is the sound of direct current!   

Try measuring for DC on your output patch cord with effect on/off.  There SHOULD be none, < a few mV. I'd bet a cup of coffee you'll see some DC when it's on.    Once that's been "rectified" (no pun intended), the buzz should go away.    Suspect that indicator LED connection at the switch putting voltage on the output wiring, or a missing/bad output cap on the Tonemender....

[jacobyjd]

I'd echo the DC issue--at least by how it sounds.

And yes...that Champ sounds glorious. Wow.

[jimmybjj]

Thanks for replying guys. I only had a few moments to debug before the wife had me do other "more important things" but I only had .03v of dc on the output. Well, I decided to strip it down to it most basic components, connected to the input and output of the board. I discovered I had a intermittent DC jack, so there was one problem. It seems to work at lower volumes now but when I turn the volume on the pedal up, I get weird doubling (almost like a green ringer)  any suggestions?

Thanks for the compliments on my champ. That was a project earlier this year, my first scratch amp build.

[GibsonGM]

Could be the opamp.  Are you using a TL072?  There is a more 'rail to rail' one, the NE5532 I think (it's mentioned on ROG's site) that might stay cleaner longer.    Could have a few causes for that freq. doubling.   Too hard of an input driving it (add series resistor), too saggy voltage supply (try it on its own w/new, fresh battery).  It could be a miswiring in the circuit somewhere, leading almost to a rectification or cutoff (how about the bias supply? Take some voltage readings everywhere you need a VRef connection....you'd get weird distortion if it was wrong). 

OTOH, it seems like maybe it's NOT the pedal, if you don't get it on lower volumes - the pedal is always 'working on 10' internally, after all.  That could be blocking distortion WITHIN the amp. Try the pedal with another amp (maybe a SS one, uck).  Try other pedals with the amp, too.  Might need to add some new grid stoppers in that baby to cut that down! 
If you have a BOSS pedal, put that after the Tonemender >> amp.  See if that does anything.  Maybe the BOSS buffer will have some effect (they are buffered even when off, so you don't have to turn it on, just make sure it has power).

So there are a few places to at least have a look, IMO....work simplest to most difficult.

Interesting problem you got there, Jimmy, I'll follow this one! 

~Mike

[GibsonGM]

Another thought occurred to me while busting my @ss at work last night....if your amp is home made, what value are your input grid-stopper resistors?  Any kind of input caps in there? Probably not, tube amps don't generally use them, but....
Something wrong at the input of the amp could do this sorta thing, too. That kind of 'rectified' sound makes me thing blocking distortion.  But if it doesn't do it with other pedals, perhaps you should stay outside the chassis for now, lol.   How does the amp sound with a BIG booster cranked into it? That should tell you pretty fast!

[jimmybjj]

Could be the opamp.  Are you using a TL072?  There is a more 'rail to rail' one, the NE5532 I think (it's mentioned on ROG's site) that might stay cleaner longer.    Could have a few causes for that freq. doubling.   Too hard of an input driving it (add series resistor), too saggy voltage supply (try it on its own w/new, fresh battery).  It could be a miswiring in the circuit somewhere, leading almost to a rectification or cutoff (how about the bias supply? Take some voltage readings everywhere you need a VRef connection....you'd get weird distortion if it was wrong). 

OTOH, it seems like maybe it's NOT the pedal, if you don't get it on lower volumes - the pedal is always 'working on 10' internally, after all.  That could be blocking distortion WITHIN the amp. Try the pedal with another amp (maybe a SS one, uck).  Try other pedals with the amp, too.  Might need to add some new grid stoppers in that baby to cut that down! 
If you have a BOSS pedal, put that after the Tonemender >> amp.  See if that does anything.  Maybe the BOSS buffer will have some effect (they are buffered even when off, so you don't have to turn it on, just make sure it has power).

~Mike

I've tried multiple pedals with the champ and they all work with the tonemender exception. I am using a variable wall wart supply for power, I've tried using a battery as well with the same results. I won't be able to get back to the house until monday, but I intend to take some Vref measurments.

As far as the amp, it is a vanilla aa764 champ with the 68k grid stoppers on V1 pin 2. The only deviations from the original are a extra 33k grid stopper on V1 pin 7 and the mica cap is 150pf rather than 250pf. I will give the BOSS buffer a try on monday.

Thanks again for your help, Jim

[GibsonGM]

Sure, let us know how it works.   Weird problem, but it sounds Tonemender-based rather than amp, then...

[slacker]

Sounds like a ground problem to me. In the video it looks like you're powering the tonemender and the Ruby off the same powersupply so it will possibly work even if the grounds in the tonemender are not connected properly because the pedal and the amp are both connected to the same ground through the DC leads.
If there's a problem with the grounds though and you connect it to the Champ because they aren't already sharing a ground you'll get problems, or something like that anyway.

Make sure the sleeves of both the input and output jack on the tonemender are connected back to the ground on the DC jack.

[jimmybjj]

Sounds like a ground problem to me. In the video it looks like you're powering the tonemender and the Ruby off the same powersupply so it will possibly work even if the grounds in the tonemender are not connected properly because the pedal and the amp are both connected to the same ground through the DC leads.
If there's a problem with the grounds though and you connect it to the Champ because they aren't already sharing a ground you'll get problems, or something like that anyway.

Make sure the sleeves of both the input and output jack on the tonemender are connected back to the ground on the DC jack.

I'm not sure were it was but this was my solution. I tore out all of the ground wiring and install all new wiring. And everything fired right up. Thanks for everyone help.