DOD - FX22 Vibro Thang  [schematic]

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sikheazdraf
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Post by sikheazdraf »

hi everyone i was wondering if you guys can help me with my DOD fx22 Vibro Thang
i got it cheap and has issues with its bypass.. etc...
i think there's problems with the wirings and etc...
i hope that somebody would help me
and could be kind to post gut shots of the insides of the pedal
and also the schematic.. thanks!..
:)

my vibro thang looks exactly like this:
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puppiesonacid
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Post by puppiesonacid »

check out schematic heaven. I believe its there. if not pm me. I might have it in my dod folder.

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modman
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Post by modman »

schematic is not at schematicheaven, might be worth taking pictures of the pcb even if the wiring is messed with.

moved to request
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Fuzzer
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Post by Fuzzer »

puppiesonacid wrote:check out schematic heaven. I believe its there. if not pm me. I might have it in my dod folder.
If you have it why not post it?
The Freestompboxes Forum search function is soo great, use the search function..., the S E A R C H function.

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sikheazdraf
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Post by sikheazdraf »

modman wrote:schematic is not at schematicheaven, might be worth taking pictures of the pcb even if the wiring is messed with.

moved to request
yep i cant find it there :(
thanks...!

anyway here's the gut shot of my DOD and the wiring. i don't know what's wrong with it though :( :oops:
Image
hope i could fix it with the help of you guys. thanks!

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puppiesonacid
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Post by puppiesonacid »

Fuzzer wrote:
puppiesonacid wrote:check out schematic heaven. I believe its there. if not pm me. I might have it in my dod folder.
If you have it why not post it?

cuz I was at work when I posted :roll:

checked my folder... no such luck. don't know where I've seen it but I know its out there somewhere. If i come across it, I'll post it.

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lolbou
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Post by lolbou »

The cut yellow wire seems weird to me, unless it's factory done...

Where's the switching system?

Is the switching like the boss pedals? Is it related to this yellow wire? Is Q4 and its neighbour part of the boos-like switching system?
- Are you a mod or a rocker?
- Uh, no, I'm a mocker.

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sikheazdraf
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Post by sikheazdraf »

lolbou wrote:The cut yellow wire seems weird to me, unless it's factory done...

Where's the switching system?

Is the switching like the boss pedals? Is it related to this yellow wire? Is Q4 and its neighbour part of the boos-like switching system?
i dont have any idea sir if the wire is factory done.
the switching system is found at the other side.
sorry but i dont really know a lot about electronics though :(
my friend's the one who'd help to work on this though. hehe
but we dont have an idea yet.. how.. hehe

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Post by borislavgajic »

can you post some pictures of copper side ...

thanks

boris

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sikheazdraf
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Post by sikheazdraf »

borislavgajic wrote:can you post some pictures of copper side ...

thanks

boris
here they are..
Image
Image
Image

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sikheazdraf
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Post by sikheazdraf »

help! :cry:

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lolbou
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Post by lolbou »

It looks like a FET switching (nothing mechanical here).
sikheazdraf wrote:has issues with its bypass.. etc...
Can you detail your issue? Always on? Always bypassed? LED always on, or changing its state, but with no effect on the sound??
- Are you a mod or a rocker?
- Uh, no, I'm a mocker.

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Post by Dirk_Hendrik »

lolbou wrote:It looks like a FET switching (nothing mechanical here).
Naturally, It's a DOD in "modern" style ;)
Is that a 4011 or a 4007 I see. Most DOD's have a 4007 vor their bypass switching/
lolbou wrote:
sikheazdraf wrote:has issues with its bypass.. etc...
Can you detail your issue? Always on? Always bypassed? LED always on, or changing its state, but with no effect on the sound??
My Q exsactly
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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Post by Dirk_Hendrik »

4007.
Meaning that for the functioning of the bypass system about any DOD schematic that uses a 4007 applies.
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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sikheazdraf
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Post by sikheazdraf »

lolbou wrote:It looks like a FET switching (nothing mechanical here).
sikheazdraf wrote:has issues with its bypass.. etc...
Can you detail your issue? Always on? Always bypassed? LED always on, or changing its state, but with no effect on the sound??
here it is.. sorry for the bad quality..
http://tinypic.com/player.php?v=bjsi1&s=5
you could hear that when the pedal is chained theres a BIIIIG drop in volume!.. even without engaging it!..i think its the bypass?
and my humbucker equipped guitar sounded like a single coil guitar. :(
see the difference between when the DOD is chained and when the guitar is directly pluged in the amp.

thanks guys! :P

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sikheazdraf
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Post by sikheazdraf »

help! :|

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Post by puppiesonacid »

impedence mismatching??? idk... thats wierd...

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Post by Fuzzer »

I'd put the blame on the Dual Opamp, because that's the one affecting the signal when the effect is activated, as well as when it isn't.

This is a rough guess, of course, but Dirk Hendrik's appreciation is just spot on, you should dig some DOD schematics from that series to have a better approach.
The Freestompboxes Forum search function is soo great, use the search function..., the S E A R C H function.

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sikheazdraf
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Post by sikheazdraf »

Fuzzer wrote:I'd put the blame on the Dual Opamp, because that's the one affecting the signal when the effect is activated, as well as when it isn't.

This is a rough guess, of course, but Dirk Hendrik's appreciation is just spot on, you should dig some DOD schematics from that series to have a better approach.
thanks sir.. what should i do with it sir?

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Post by Fuzzer »

Take it out, put a socket in and then try another one.
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