EH - Clone Theory ( versions )  [schematic]

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Re: EH - Clone Theory ( versions )

Postby modman » 09 Aug 2016, 12:53

Factory schematic
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Re: EH - Clone Theory ( versions )

Postby pinkjimiphoton » 09 Aug 2016, 14:23

thanks modman,
according to this, marked "final version" perhaps i am right. i remember the vib chorus predating the "edge" switch... this shows a 1024 in CT with the chorus vibrato switch as a blend pot, which i never saw ever.
leave it to eh to fuck with our heads 40 years later ;)
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Re: EH - Clone Theory ( versions )

Postby Zack-stomp » 21 Sep 2019, 23:06

Hello. I have a Clone Theory with a green PCB marked EH3000 and am seeking the correct schematic and/or a tip on its use.

I have the Edge switch, and when on, the chorus/vibrato pot doesn’t do anything. When off, the pot controls that balance. Is this normal? My edge switch is dual pole and one pole runs to that pot... but the schematic would help me make sense of it.

The schematics I’ve found are for the EH1317 board and show a single-pole edge switch.

It seems like the schematic I need might be in this thread (from Scruffy) but Photobucket has blurred it beyond recognition.

Thanks much for any help!
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Re: EH - Clone Theory ( versions )

Postby Zack-stomp » 21 Sep 2019, 23:09

I mean Scruffie, sorry.
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Re: EH - Clone Theory ( versions )

Postby pinkjimiphoton » 22 Sep 2019, 06:00

the schematic at the top of this page is correct for how the unit is with the sad1024 chip with the edgs. i don't have this version anymore, so can't help much beyond that, but its most definitely NOT RIGHT as you describe it. the edge should be like a hissy treble boost.. all it does is lift the cap that sinks all the noise to ground, pretty much. i would check voltages on the SAD chip. be careful. them things are unobtanium but i suspect from your description that the unit is not working, and the bbd is likely given up the ghost. it would still work, as a buffer kinda,,, but no pitch bending or real chorusing.
we needs voltages mate
if ya wanna squash that bug
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Re: EH - Clone Theory ( versions )

Postby Scruffie » 22 Sep 2019, 18:18

The 3000 PCB was the MN3007 model, seems it was more prevalent than the odd unit to have the Edge labelling on a Vibra-Flange model.

What you're describing is totally normal, the Vibra-Flange mode hardwires it in to vibrato with added feedback.

I thought I read the other day that if you save the files from photobucket they're still visible, but anyway, you can find it on page 4 here https://lectric-fx.com/wp-content/uploa ... s_V1.2.pdf

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Re: EH - Clone Theory ( versions )

Postby pinkjimiphoton » 22 Sep 2019, 19:16

they all have vib/flange vib/chorus settings, at least the ones i've owned.
the edge switch shouldn't disable anything but the cap to ground shown in the schematic, should have nothing to do with stopping any of the other functions, memory's dodgy of course, but... seems a little weird!
the only ones i saw with the edge switch were the sad models, not the 3007 ones bros
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Re: EH - Clone Theory ( versions )

Postby Scruffie » 22 Sep 2019, 19:33

It was covered at the start of this thread, Jimi, there were vibra-flange (MN) units stuck in enclosures with the Edge labelling, confusing but that's how EHX rolled.

Only the SAD model had an actual Edge Function, so even though it says Edge on the box, with a 3000 PCB, it's Vibra-Flange. The SAD models did not have any flange ability.

The Edge function reduces the de-emphasis filtering on the SAD model, on the MN models, the pedal gets hardwired to vibrato and feedback is added to the input stage.

So to clarify, you can't count on the enclosure to tell you which variant of the pedal you have and the description Zack gave is perfectly normal behaviour.

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Re: EH - Clone Theory ( versions )

Postby Zack-stomp » 22 Sep 2019, 23:15

Thanks both for your thoughts and also the rebuild schematic, Scruffie. It sounds good, but I just couldn’t find any demo or documentation to confirm the switch function. Glad this seems normal.
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