Dr. J Effects - D50 Green Chrystal Overdrive

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Frabbio
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Post by Frabbio »

I have a Dr.J Green Crystal Overdrive here with me, it's a Timmy clone.

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modman
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Post by modman »

Frabbio wrote:I have a Dr.J Green Crystal Overdrive here with me, it's a Timmy clone.
Sorry, but it doesn't work like that. Do you think it's a Timmy, or have you traced it? Please provide some gut shots of both side of the pcb... right now, it's just hearsay.
Same goes for your previous remarkt in the thread:
Frabbio wrote:I got a Joyo US Dream here with me to make some modification, and i can confirm it's a Riot clone.
The clipping section is only asymmetric in the Joyo pedal.
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Frabbio
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Post by Frabbio »

I have traced it, as i did for the Us Dream.
Actually i already did some tweak on the values of the bass/gain structure. Here are 3 photos of the Green Crystal, if you compare the values you see with the Timmy schematic, you can see it's an exact clone. Only difference, tone controls are wired backwards respect to the original. I can't post US dream guts because i don't have it anymore.

Image

Image

Image

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Post by modman »

I had a hard time finding a verified Timmy schematic... closest I could find was this: viewtopic.php?f=7&t=140&p=43393&#p43393, but I haven't plowed through the remaining 17 pages of the thread.
I understand you looked at the values, but that's not tracing a pedal... it means analysing the pedal in question without preconceived ideas. Or at least provide good pictures of both component and trace side...
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Frabbio
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Post by Frabbio »

I did the tracing,but I can't post detailed photos of both sides because I did some mods to both sides of the pcb, and I don't want to reverse them!
I should have took photos before i started modding it!
However looks like the pedal is based exactly off the schematic you linked (which i think is verified), with the already said difference about tone control wiring and a dpdt instead of the dipswitch.

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vikingz
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Post by vikingz »

How does it work ?.

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