EHX - Mini Q-Tron  [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 »

click for a larger pic
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Bernardduur
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Post by Bernardduur »

I've already traced that unit

Will search
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Dirk_Hendrik
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Post by Dirk_Hendrik »

Don't bother. It's in the big EH archive that was to fe found online untill the Ork came by.

As said, PM me with a mailadress if you need something from that archive.
Sorry. Plain out of planes.

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Post by bajaman »

I had one in for servicing recently - took some high res pictures of the solder side etc. - anyone want to build one - I have the artwork almost cloned - 75% done. :lol: :wink:
bajaman

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Post by Bernardduur »

Dirk_Hendrik wrote:Don't bother. It's in the big EH archive that was to fe found online untill the Ork came by.

As said, PM me with a mailadress if you need something from that archive.
K, I won't post it :)
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Post by lohstah »

i borrowed a very early unit from my music store when they had just come out and it had the hp and lp the wrong way round, so hp was really lp and vice versa. is it still that way ?

cheers,
lohstah

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Post by Bernardduur »

lohstah wrote:i borrowed a very early unit from my music store when they had just come out and it had the hp and lp the wrong way round, so hp was really lp and vice versa. is it still that way ?

cheers,
lohstah
No; all units I had in were in the right order
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modman
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Post by modman »

Thanks guys!

I got it in a trade for a DIY TS. Just took these pics as I had to dissemble it anyway. I'll show you why:

Image

After a trip on acetone yesternight, I got it back to this now:

Image

Also put the knobs in some acetone -- they didn't take it so well, they started dissolving. :slap:

With regard to the EH archive, Meanderthal did us a favour in the POG thread. Everybody could contribute by taking the zip and uploading it to different free hosting services. Or maybe we should find some Japanese free upload site, perhaps it'll last longer when hosted there.

The Qtron (not micro or mini Qtron) schematic in that collection shows 4558 opamps where mine has TLC2262CP, and gets fed 18V to pin 87 of the first IC. Mine just runs off 9V
bajaman wrote:I had one in for servicing recently - took some high res pictures of the solder side etc. - anyone want to build one - I have the artwork almost cloned - 75% done. :lol: :wink:
bajaman
:shock: :D Baja, you must be clairvoyant!
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Post by bajaman »

Okay Modman - as you already have the enclosure and we all have the mini Qtron schematic, I will have the artwork completed for the coming weekend :wink:
cheers
bajaman

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modman
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Post by modman »

Bajaman, there is no hurry at all, just let me know when you get round to it. I should first try how it sounds *without the artwork* :D
Being a funk junk, I cannot see how I could ever do without this pedal.
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Post by lohstah »

aarrrghh! of course i meant the micro q-tron with my post about the wrong lettering...

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Post by polarbearfx »

Is this thing worth building? I love the bigger qtron. Some of the components look pretty hard to find. I guess a diy version might be hip.

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Post by modman »

Great stuff, Baja, incredible. Do you know of any available verified MiniQtron schematics? Have been searching but didn't find any. If we do, this could go into the projects folder.

thanks!
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Post by bajaman »

Hi modman
i have the factory schematic - it was in the archive that AG discovered - let me know if you have not got it and i will email it to you
cheers
bajaman

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Post by Nikifena »

Thanks banja.

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Post by floris »

Sorry to bother you but I'm looking for schematics of the EH mini QTron (perhaps also a regular QTron if you have it).
I've looked for it on freestompboxes, diystompboxes and some googling but can not find it.
I have a mini QTron and want to add a control to adjust the attack of the envelope follower section.
I did find and download some PCB and Layout from bajaman, thanks!

I saw some reference to a site containing all factory EH schematics but that one is down, probably just too good to be true. Can somebody post, host that zip file containing all those schematics? Would be much appreciated.

Floris.

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Post by RLBJR65 »

Qtron, MiniQtron and much much more :D

(file down)
Last edited by modman on 25 Apr 2008, 19:42, edited 1 time in total.
Reason: admin: removed dead link, check below

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Post by floris »

The file has been removed! :cry:
"An error has occured:
This file has been deleted.
Reason: THIS FILE IS FORBIDDEN TO BE SHARED! Complaints received."
Can somebody re-post / re-host it please?

Flo.

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