Fulltone - OCD  [traced]

General documentation, gut shot, schematic links, ongoing circuit tracing, deep thoughts ... all about boutique stompboxes.
V1nce69
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Post by V1nce69 »

Intripped wrote:nice work!
just a little note:
in your drawing, 2N7000 pins are named wrong
Thanks for your comments. And yes I have just seen my mistake. So here is the corrected layout:
OCD pcb revision 1.4 layout
OCD pcb revision 1.4 layout

FuzzMonkey
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Post by FuzzMonkey »

Interesting reading regarding the new Fulltone OCD V2.0:

http://mailchi.mp/fulltone/fulltone-mas ... 613f41cc4e

caspercody
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Post by caspercody »

Would love to see that enhanced bypass layout.

Thanks for the article link!

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Post by FuzzMonkey »

caspercody wrote:Would love to see that enhanced bypass layout.

Thanks for the article link!
I'm sure on will be cracked open soon enough.

bugg
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Post by bugg »

I traced the new V2 version this weekend. Will post the schematic once it's cleaned up and verified. :mrgreen:

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Post by FuzzMonkey »

bugg wrote:I traced the new V2 version this weekend. Will post the schematic once it's cleaned up and verified. :mrgreen:
Thanks for your efforts Bugg. I look forward to seeing the schematic.

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Post by POTL »

Input and output buffer on jfet probably the main differences
The scheme of the bypass is more interesting

chuckd666
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Post by chuckd666 »

Wait, so let me guess.. now true bypass isn't exciting, they're going to start selling buffered bypass as a new thing? :o

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Post by POTL »

chuckd666 wrote:Wait, so let me guess.. now true bypass isn't exciting, they're going to start selling buffered bypass as a new thing? :o
Not really
These are 2 bypass modes true / buffered which are switched by the built-in toggle switch.
The buffer role in the bypass plays the output buffer on Jfet (as I understood from the description)
I'm interested in the switching system with SPDT or SPST toggle switch

bugg
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Post by bugg »

POTL wrote:I'm interested in the switching system with SPDT or SPST toggle switch
The toggle switch is DPDT. I'll post the schematic tonight. I have PCBs on order, the first batch will use smd jfets because they're much easier to source.

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Post by POTL »

bugg wrote:
POTL wrote:I'm interested in the switching system with SPDT or SPST toggle switch
The toggle switch is DPDT. I'll post the schematic tonight. I have PCBs on order, the first batch will use smd jfets because they're much easier to source.
DPDT?
Then I know how it works =)
Although we can see there is still some way.

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Post by POTL »

bugg wrote:
POTL wrote:I'm interested in the switching system with SPDT or SPST toggle switch
The toggle switch is DPDT. I'll post the schematic tonight. I have PCBs on order, the first batch will use smd jfets because they're much easier to source.
Hi, when will the schematic appear? :D

bugg
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Post by bugg »

Sorry man, haven't forgotten about you! Had to deal with some car repairs this week so been busy.

The trace is done, PCB is drawn, I just need to clean up the schematic and export to an image then I'll post it.

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Post by POTL »

bugg wrote:Sorry man, haven't forgotten about you! Had to deal with some car repairs this week so been busy.

The trace is done, PCB is drawn, I just need to clean up the schematic and export to an image then I'll post it.
OK
Thank you bro
In fact, I do not need a fee. I'm interested in the circuits themselves.
1) I like to breed boards myself
2) The scheme is interesting from the sports interest, I do not plan to collect a clone for myself or for sale, I'm just curious

bugg
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Post by bugg »

Schematic.png
Here ya go, I'll upload a pinout for the 3PDT shortly. I have PCBs ready to go for this if anyone wants em.

I'm aware that Q5 appears to be upside down, I reconfirmed this multiple times, it is correct. Since these are 2N5457 the Drain/Source is interchangeable.

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Post by POTL »

bugg wrote:
Schematic.png
Here ya go, I'll upload a pinout for the 3PDT shortly. I have PCBs ready to go for this if anyone wants em.

I'm aware that Q5 appears to be upside down, I reconfirmed this multiple times, it is correct. Since these are 2N5457 the Drain/Source is interchangeable.
thank you very much
in the description it was said that there will be buffers, and he added boosters lol

boukman
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Post by boukman »

Hi guys!
So is that buffer worth the effort?I already have an OCD clone.All that talk about Class A buffers at the product description..I mean is it really much better than a simple fet buffer in the dynamics department?
Can someone post the schematic of only the buffers section,or a tagboard?
Thanks!!!

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Blend
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Post by Blend »

This new version is a maquillage operation. When the sales are jammed, the product was to be redone, the stated goal was to retire the fulldrive with the improved ocd and strange case pops up buffers like fulldrive, morning glory, ts etc etc and takes a bit here and there, like the snake that continues to bite its tail. An input Fetzer Valve, the disappearing germanium diode, and the 1k resistance on the tone as on the od Glove electro harmonix clone or other mods experienced on this forum. I bought a Ocd to resell it after cloning it and although it was not the best pedal in the world it sounded good, I will apply these novelties to the circuit and see if it's worth it.

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Post by Groovenut »

POTL wrote:
bugg wrote:
Schematic.png
Here ya go, I'll upload a pinout for the 3PDT shortly. I have PCBs ready to go for this if anyone wants em.

I'm aware that Q5 appears to be upside down, I reconfirmed this multiple times, it is correct. Since these are 2N5457 the Drain/Source is interchangeable.
thank you very much
in the description it was said that there will be buffers, and he added boosters lol
Yeah, those aren't necessarily buffers and I would hardly call them boosters either. Maybe an inverting amplifier that provides unity ( 0.37dB of gain). I suppose you could call them impedance converters. I agree with the smoke and mirrors assessment so marketing can say it's something new. I doubt most could hear (or measure) a difference from the original at normal guitar levels. Of course if you hit the input with anything over the pinch off voltage of Q5 (Q6), you'll get asymmetric clipping from both Q5 and Q6.

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bajaman
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Post by bajaman »

I had some boards made and built one to satisfy my curiosity and it sounds good - I think the enhanced bypass buffers are a nice touch - I will most likely leave the small switch in the enhanced position :wink:
PM me if you want to purchase a spare board :wink:
cheers
bajaman
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