Can I get a little help with my Ampeg Scrambler?

[tiges_ tendres]

eliminate the switching all together.  Just wire the effect up directly to the in and out jacks.  At least to test it.  No point in burning up a switch because of resoldering.

All jacks are different, but it seems to me like you have your jacks wired incorrectly.  Usually, stereo jacks are wired like this:

With the portion of the stereo jack where you insert a guitar cable facing away from you, the lugs I'll number 1 through 3.

Lug 1 should be going to the board in (or switch in)
Lug 2 Should be ground
Lug 3 is also ground, but for the negative lead of the battery.

That much is evident from the gaussmarkov wiring diagram you followed, but you dont have it wired up as in the diagram.

[peps1]

With the portion of the stereo jack where you insert a guitar cable facing away from you, the lugs I'll number 1 through 3.

Lug 1 should be going to the board in (or switch in)
Lug 2 Should be ground
Lug 3 is also ground, but for the negative lead of the battery.

That much is evident from the gaussmarkov wiring diagram you followed, but you dont have it wired up as in the diagram.

Keep getting contradicting comments on the lug wiring.....IMHO it is the same as gaussmarkov wiring diagram with both jacks having the TIP lug hooked up to the switch (white wires) then the stereo jack has a ground from the switch though to the board both meeting on the Sleeve Lug (PINK/green ongaussmarkov), where a ground wire connects back to the mono jacks ground (black crocodile clip in my pic)........is that not the same?




Can someone treble check my transistor placement, as im getting some horrible sounds as soon as i hit the first one wit the audio probe!



Q1 = MPSA14
Q2 =2N3904
Q3 =MPSA14
Q4 =MPSA14

[The French connection]

flip all your trannys! Same pinhole on board but mirrored orientation...

Dan

[peps1]

Thanks Dan, will flip them round 180 (and write a big note telling me not to read the pin out upsidedown on my tranny box).

Its almost as if it was the very first thing your suggested 

[peps1]

Still no luck, going to do a whole new rebuild tomorrow from scratch MAKING SURE the transistors are the right way round (thanks Dan  )... I think iv just mashed up the tracers with all the re soldering.....and too sleepy and pissed with it to redo tonight!

Think I will try another switch layout......so any recommendations welcome   

[The French connection]

Woooo! It looks like you've grounded the wrong lug on your stereo jack (Input): the alligator clip should go on the center lug, just as on your output. Try that before rebuilding it completely. In the actual configuration you have, you ground the input...Test with an audio probe now that the trannys are properly oriented.

Bonne nuit!

Dan

Edit: The switching layout is the one i always use, and never got problem with it. It's perfect for high gain circuits...

[tcobretti]

Yeah, don't rebuild before you audioprobe.

[peps1]

J'en ai ras le bol !

Had to do a rebuild as the tracks were to messed up after trying to switch the transistors round.

BUT STILLLLLLLLLL NOT WORKING!


(the blue input wire came detached when taking the photos, not testing)







And Im not picking up anything on the PCB with the audio probe.....

[The French connection]

Your jack look wired properly, and your trannys well oriented. Can we see the traced side of the PCB in closeup shot? Moreover, is the layout you use is verified? Is it from Tonepad? Did you audio-probed it? Does the input get in the board at least? Follow the debugging procedure, it's one of the best way to get rid of basic problem.

Lâche pas la patate!  

Dan

Edit: HEYYYYY! R12 must be 220K not 220R? I see red/red/brown! i'm i wrong? Check all your value on your board!

[peps1]

You were right, i had the 220k and 220 round he wring way........have switched now 

Still no effect, but i did a test with the audio probe, starting with the switch.....and am getting clean guitar out of the yellow wire....but relly not sure how to follow it round the PCB (and is the yellow not the OUT, thought it should be coming thogh the blue INPUT wire???)

But here is a pic of the underside, with the layout.....I cont only see one problem at the bottom right, on the ground track....but iv used a jumper over that....and still no joy

[The French connection]

Clean your board and reflow all your solder properly. Take an knife (exacto) and clean every space between solder that don't have to be connected. Take your audio probe and start from the input ->then before C1 -> after C1 -> Q1 base -> and so on... until you loose the signal. Where you loose it, you have a problem, correct it and continue with the probe 'till the output. Tha ground trace look thin on the down right corner...

don't give up!

Dan

[peps1]

start from the input ->then before C1 -> after C1 -> Q1 base -> and so on... until you loose the signal.

Thats the strange thing Dan, Im getting nothing from the Input.....But Im getting audio from the output then the effect switch is on?

[tcobretti]

Take the switch out and see if the pedal is working.  If it is, then the problem is with your switching.

This is how I wire my pedals.  It will work the same as your version, but it easier to understand and harder to screw up.  BTW, you should use a continuity tester to be sure the switch is working like you think it is.

[The French connection]

Thats the strange thing Dan, Im getting nothing from the Input.....But Im getting audio from the output then the effect switch is on?

Do that!

eliminate the switching all together.  Just wire the effect up directly to the in and out jacks.  At least to test it.  No point in burning up a switch because of resoldering.

I know it sounds like a stupid question but, did you powerup your circuit when testing? Did your battery is plugged? No offense, it happens...to me to say the least! 

[tiges_ tendres]

Your jack looks really bent compared with most. Perhaps you have access to some like the ones pictured above.  Those are they type most of us are more familiar with dealing with.

Also, on your pcb there are few spots where it looks like you could have track breaks.  I've circled them below.  Might be worth just fixing those to be on the safe side.

[peps1]

Take the switch out and see if the pedal is working.  If it is, then the problem is with your switching.

Ok taken the switch out the loop, and i get a sound though my pedel......but its a really clean sound with the BLEND pot acting as a volume control?

I know it sounds like a stupid question but, did you powerup your circuit when testing? Did your battery is plugged? No offense, it happens...to me to say the least! 

Not a silly question at all........and yes....i checked the little red LED but it is something i would do! 

Also, on your pcb there are few spots where it looks like you could have track breaks.  I've circled them below.  Might be worth just fixing those to be on the safe side.

Yes, solder linked both the spots you marked, but alas no change

[peps1]

YAY!!!!!

Got it working, without the switch, turns out the Q2 2N3904 needed flipping.

Seem to be getting alot of background noise (with any gain on the amp)......any way to deal with that?

Going to try hooking it up to the switch now............Sounds INSANE!   

[The French connection]

Awesome! Bravo! I think you've learn alot in the process. So what's the next one?

Bonne soirée!

Dan

[tcobretti]

Nice job!  Successful debugging always comes down to not giving up. 

If you keep at it, you'll almost always figure it out.

[peps1]

It was really frustrating to be stuck on one little circuit for 3 days...but I got some really valuable lessons from it esspacialy the Audio-probe!

Now I get to do the fun part, and make the enclosure   

Next circuit is the Phaser 90 from tonepad, have etched the PCB and have all the parts, except a 500k pot.

Thank your all so much for the help, and more importantly the patience!