boss dm-2

[freak scene]

seems to be working, but the LED isnt now.  i had retraced that portion of the board before, but i guess not far enough.  i havent gotten to plug it in yet (the little one is sleeping) but it gets a signal oscilloscope.

[oskar]

...but the LED isnt now.

Awwwh... give me a break...     

r41

Put that thing back where it came from, or so help me!   

i had retraced that portion of the board before, but i guess not far enough.

What part and how?... but clearly far enough, it was a closed cirquit before.   

Which parts did you bridge now? Did you do anything else to it?

Measure continuity C37 to D3, pad 10 to D3
Or give us D3 voltage reading. ( referenced to ground ) I'ld rather see both   
If it isn't getting any, bridge from V+ to D3. ( george's suggested bridge should do it )
Now I'm going to eat filmjölk.

[freak scene]

What part and how?... but clearly far enough, it was a closed cirquit before.   

Which parts did you bridge now? Did you do anything else to it?

Measure continuity C37 to D3, pad 10 to D3
Or give us D3 voltage reading. ( referenced to ground ) I'ld rather see both   
If it isn't getting any, bridge from V+ to D3. ( george's suggested bridge should do it )
Now I'm going to eat filmjölk.

i re ran the trace using a stripped solid 22 gauge copper wire from the power in to c37 hitting r41 as well, then did the same thing to the ground side to the point you mentioned earlier (d5 i think). 

the whole circuit board seems to be working (im getting signal from the clock and the bbd etc on my scope.)  just is stuck bypassed.  i havent opened it up yet.  im hoping its just the switch as it was a bit intermittent before.

[oskar]

+1 bridge it... I would bridge all the way to C37 though. Your fix is around D3 and that's where the flip-flop gets it's voltage right now.
Via the LED.

Sorry, I'm not a native english speaker so I'ld like to clarify a couple of things.
The first sentence means bridge C37 - side to ground and C37 + side to V+. Nothing else.
With sentence no. 2 I'm trying to logically motivate why. Your in your fix. is George. You should have listened to George. He drew a fine map for you.
http://www.geocities.com/george_giblet/effects/dm2_repair.jpg
In any case there was just two wires needed.

i re ran the trace using a stripped solid 22 gauge copper wire from the power in to c37 hitting r41 as well...

You connected R41 to V+?
If you've connected R41 to V+ then please do unconnect it before you do anything else.
Look up R41 on the schematics with main goal to try and find it's connection with V+.

then did the same thing to the ground side to the point you mentioned earlier (d5 i think).

I think not. Turn your magic eightball off and think again...

the whole circuit board seems to be working (im getting signal from the clock and the bbd etc on my scope.)  just is stuck bypassed.  i havent opened it up yet.  im hoping its just the switch as it was a bit intermittent before.

Think V+ without resistance to Q6 base...

[freak scene]

Sorry, I'm not a native english speaker so I'ld like to clarify a couple of things.
The first sentence means bridge C37 - side to ground and C37 + side to V+. Nothing else.
With sentence no. 2 I'm trying to logically motivate why. Your in your fix. is George. You should have listened to George. He drew a fine map for you.

that is what i did.  i did what george said.
http://www.geocities.com/george_giblet/effects/dm2_repair.jpg

i must be explaining it wrongly.  my apologies.

[oskar]

I sort of knew before I posted that I hadn't got it right so... sorry.   
also I got sloppy. I didn't read your post with the gutshots properly because I just saw a picture I had just seen over at another forum.
So I thought it was gutshots of another unit for reference.
This is what your pedal was doing one year ago... ( bottom of the thread )
http://www.bossarea.com/forum/topic.asp?TOPIC_ID=3248

... So, is that red wire still in there?
What pads is/was it bridging?



oskar

[freak scene]

I sort of knew before I posted that I hadn't got it right so... sorry.   
also I got sloppy. I didn't read your post with the gutshots properly because I just saw a picture I had just seen over at another forum.
So I thought it was gutshots of another unit for reference.
This is what your pedal was doing one year ago... ( bottom of the thread )
http://www.bossarea.com/forum/topic.asp?TOPIC_ID=3248

... So, is that red wire still in there?
What pads is/was it bridging?



oskar

well the pedal was working fine when i got it (2 weeks ago).  my friend gave me the link to the thread he posted asking about the red wire.  i took the red wire off (it was bridging v+ to R41).  i re did the broken traces and installed a reverse polarity protection diode and it didnt work.  i went through this whole thing in the thread to find out i didnt go far enough with the trace repairing.  the circuit works, the pedal passes clean signal, but now wont turn on (no echo).  i tested the momentary switch and its good, havent gotten past that point cause i got busy with some other things.

but i need to trace out the bypass circuit and see whats not working.

any ideas or pointers?  should i try to make it a true bypass pedal?

[George Giblet]

I thought it was all working except for the LED?   You could try replacing the LED and/or the transistor driving it, they may have been damaged.

[oskar]

OK!
Q6 should be pretty toasted don't you think? The red wire connected to it's base so it was shorted to ground.
Change Q6!