DOD - FX15 Swell Pedal  [schematic]

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oscarv77
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Post by oscarv77 »


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Post by Goop_buster »

oscarv77 wrote:DOD-FX15

:?:
Nice pictures :D

I do not think it is hard to trace but you may find that the 6-pin Clarex CLM50 (photocoupler, diode + light dependant reisistor inside) is somewhat obsolete or hard to obtain. I may be possible to replace with something similar like a Vactrol Optocouplers or even a similar homemade device but hard to say how close you will get.

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Post by oscarv77 »

Yeah, when I inquired about it over at DIYstompboxes, I was told the same thing about the CLM50.

I guess if there was ever anyone that could tweak, improve, and redesign that circuit it would be the gurus here.

I have the pedal for a couple more days if anyone else needs more pictures, or if anyone has any other questions.

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Post by bajaman »

What is it - compressor - distortion???
What does it sound like - is it any good??
bajaman

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Post by oscarv77 »

bajaman wrote:What is it - compressor - distortion???
What does it sound like - is it any good??
bajaman
It's a weird pedal for sure... I played around with it, and I'm not _that_ coordinated. Seems that since it's rare, people want to spend a decent amount of $$ for a DOD pedal.

It's a swell pedal, so its like an automatic volume pedal-type of thing. You hold the switch down, and you can make the notes bloom, or decay depending on the settings.

Like I said, I messed with it, but my coordination was waaaay off (I still have trouble not messing up while I "wah") :roll:

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Post by DWBH »

OMG OMG OMG!!! I saw this pedal somewhere but I thought it was digital and therefore of difficult reverse enginneering... woohoo!!

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Post by Dirk_Hendrik »

Don't bother! I've reversed that pedal somewhere 15 years ago already. Lemme find a scanner.

And djee-sis.. find a better place to host your images. This is just one pop-up circus :roll:
Sorry. Plain out of planes.

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Post by DWBH »

Hehe, Dirk Hendrik, please do!

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Post by bumblebee »

yea idk why people just dont use photobucket, its great and ive had no problems on any forum i use with PB.

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Post by Dirk_Hendrik »

Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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Post by analogguru »

Schemtic contains mistakes:

1.) The 1k output resistor should connect to the other side of the Cut/boost-pot.
2.) Between the 100k and 220k (T1/T2) should be a pushbotton to ground.
3.) The 100k pullup at T1 seems to be in reality a 10k.
4.) The Attack/Decay electrolytic seems to me a 1µ instead of 4µ7
5.) The capacitor in parallel to the 10k (in series with the LEd of CLM50) seems to be a 10n

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Post by Dirk_Hendrik »

You''re right.

I was somewhat in a hurry this morning. lemme redraw that.
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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Post by Dirk_Hendrik »

Done.
The cap is 4.7 uF confirmed. None of the photo's posted seem top show this.
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Post by DWBH »

For this pedal, is a momentary switch recommended?

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Post by Dirk_Hendrik »

Yep,

Since it's a DOD the swith used will be momentary anyway. In other pedals they add a flipflop behind the switch. In this case they don't.
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Post by DWBH »

Either a 3PDT or 2PDT, it doesn't matter right? It's the same thing as a 'normal'/'regular' pedal, but this time's gotta me momentary.

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Post by analogguru »

The cap is 4.7 uF confirmed. None of the photo's posted seem top show this.
What can be seen is the voltage rating of 50V and the same size as the 10µ/25V electrolytic. So it must be lower than 10µF and probably higher than 1µF, cause the can of the 1µF/50V is smaller... So 4µ7 seem to be the right value.

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Post by Dirk_Hendrik »

AG,

I had the bugger next to my right hand when I wrote that I confirmed the value. ;)

(It's one of the first pedals I've ever bought. Out of a box with damaged stuff, leftover stuff and other various junk. Paid an approximated 5 dollars (converted) for the thing)

The thing that does bother me is that my example does have a 3k3 resistor as upper part of the bias network. I kept it with the pedal after modification so today I confirmed that too (meaning I did not misread back in '94). And yes, it did distort easily before modification. In the photo's shown in this topic it shows the more to be suspected 22K. Error at the DOD production line?
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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Post by analogguru »

I had the bugger next to my right hand when I wrote that I confirmed the value.
Hey.....thats tricky and unfair... :!: :wink:
The thing that does bother me is that my example does have a 3k3 resistor as upper part of the bias network.
hmmm... 3k3... and 22k for the lower ?
They took the wrong resistor-belt.... that´s impossible cause the bias is only for the audio-path. Even 3k3/3k3 would be nonsense there.

You should sell your unit with the original resistor as "special-monday-edition" for collectors only..... you can get a lot of money... and with this money you can afford a modern boutique-pedal... :wink: :lol:

analogguru
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Post by Dirk_Hendrik »

You should sell your unit with the original resistor as "special-monday-edition" for collectors only..... you can get a lot of money... and with this money you can afford a modern boutique-pedal... :wink: :lol:

analogguru
Image

Perhaps... name me a modern boohteek pedal wort spending the money on. I can mention only a very few.

And am, for that reason, usually more interested in the contemporary stuff which does, occasionally, show exciting solutions to tuning to sound. Take the Ibanez Cyberdrive we discussed a few weeks ago.
Sorry. Plain out of planes.

http://www.dirk-hendrik.com

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