DOD - FX35 Octoplus  [schematic]

All about modern commercial stompbox circuits from Electro Harmonix over MXR, Boss and Ibanez into the nineties.
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modman
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Post by modman »

DOD - FX35 Octoplus schematic
DOD - FX35 Octoplus schematic
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AdiMacG
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Post by AdiMacG »

Hi,
new to this forum, looks to be full of interesting reading.
I have an old FX-35 which hadn't been used for a long time and I find now that my pedal is no longer working in either bypass or effect mode with either battery or power supply with guitar and amp plugged in.
Also no led light coming on the pedal but the stompbox.
I have found a schematic http://www.americaspedal.net/fx35/ Rev. C on the net but my pedal's PCB is Rev. F. though it could be quite similiar.
I check the stomp-switch for continuity on/off and that seems fine. Interesting link for anyone who needs to change one here http://www.americaspedal.net/fxtech/switchrepair.html

It should be something simple wrong with this pedal but if you have any suggestions or known component issues please let me know.
This Octoplus FX-35 Pedal as you know is quite old so I've checked and retouched any suspect dry solder joints. I have over 8V arriving to the PCB, whether I use a rechargeable 9V or the power supply(center positive).
I suspected a faulty diode 1N4001 (tested in-circuit) was pulling the voltage to ground and so soldered in a 1N4007 but no success. Re-tested the diode 1N4001 out of circuit, this component tested fine.
Could the input jack that controls on/off be the problem? But if it was then my pedal would still work with the PSU plugged in that doesn't depend on the 1/4" input jack.

Your thoughts please?

Regards

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atyimd21
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Post by atyimd21 »

Ok so I know better but I’ve done it dozens of times with no problems. Changing out the DOD d.c. jack. This time stupidly left the board in dril caught and pulled in grazing the circuit board. I can’t seem to find where it grazed but it worked fine before and no passes only a clean signal when engaged the pots don’t do anything noticeable. My board is Rev.I I’m posting a few pics any help here would be graciously appreciated

Proper working voltages (if anybody's got' em) would be awesome
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Last edited by atyimd21 on 11 Dec 2021, 00:14, edited 1 time in total.

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atyimd21
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my favorite amplifier: As of now? OK. Yamaha G100
Completed builds: Thanks for asking ....roughly over 250.. Some I etched myself other I bought pre-fabbed.
Location: here in America

Post by atyimd21 »

New to this so here’s another pic

Image[/img][/img][/img][/img]
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jimilee
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Post by jimilee »

Have you taken any voltages with your DMM to see if it's getting any power, and have you used the correct DC adapter? The black and silver diode should be the reverse polarity diode to protect the circuit from just that.

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