Mountainking Electronics - Megalith  [traced]

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

I have been a long time lurker here and wanted to contribute. This is the first pedal I have traced and drawn a schematic for. It would be nice to get a second set of eyes, but I only have a crappy phone camera. I can post my perf trace if need be.

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Bernardduur
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Post by Bernardduur »

Looks like something is burned........
'No more....... loud music.......'

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ringworm
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Post by ringworm »

I had been wondering about this pedal. Some guts have turned up online. Is your copy a clone or re-housed pedal?
Some random images,... none of which are mine...

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There's a trim pot on the board of that last one. It's for active pick-ups, not sure where it goes.

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Eyeofowl
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Post by Eyeofowl »

My buddy got this pedal from Wino(Saint Vitus, Shrinebuilder, etc.). The bottom plate is numbered 1 and the signature matches the one in your pic. It may have gone through some revisions by now...

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ringworm
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Post by ringworm »

Wow! That's some Pedigree!
The layout still looks the same but i couldn't say if values have changed from the pics.

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Eyeofowl
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Post by Eyeofowl »

After trying to put this together on vero, I realized there were multiple resistor errors and a wrong cap. At least I learned something... Always double check component values and use a multimeter if in doubt. I haven't done a comparison with the original, but everything is working and it sounds good. Here is the updated Schematic:

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onebuzz
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Post by onebuzz »

I was puzzled why mine did not work. I'm a touch colorblind so those metal film resistors are a bugger to read. Thanks for the revised schematic.

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destro
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Post by destro »

100ka on the output, I am assuming?

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Ice-9
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Post by Ice-9 »

Your polarity protection diode is burned out, replace it and check for shorts.
It's fairly straight forward, if you want to start it , press start. You can work out the rest of the controls for yourself !

No silicon heaven ? preposterous ! Where would all the calculators go ?

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ringworm
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Post by ringworm »

destro wrote:100ka on the output, I am assuming?
The schematic in the original post had the output pot listed as 100kB.

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Post by atreidesheir »

"Contemplate it - on the tree of woe." :Thulsa Doom

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onebuzz
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Post by onebuzz »

Just posting a circuit shot of my workalike device. Turned out pretty good.
Attachments
IMG_0035.JPG
IMG_0034.JPG

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Eyeofowl
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Post by Eyeofowl »

Ice-9 wrote:Your polarity protection diode is burned out, replace it and check for shorts.
It's in parallel. I am under the assumption that it is kind of useless to replace? I guess I could put one in series for my buddy, but I am kind of lazy.
onebuzz wrote:Just posting a circuit shot of my workalike device. Turned out pretty good.
Awesome! did you add the notch shift rotary? I was going to just wire up a Dpdt(on-off-on) with 10n, 10n, and 22n to get 10n, 20n, and 32n. Close enough I think.

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onebuzz
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Post by onebuzz »

Just added a single pole on-on switch with .01uf and .033uf.

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Post by agoldoor »

How can no one have posted a layout for this yet, or confirmed the schem yet? =)

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agoldoor
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Post by agoldoor »

Bump for a vero? =)

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IvIark
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Post by IvIark »

There you go

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"If anyone is a 'genius' for putting jacks in such a pedal in the only spot where they could physically fit, then I assume I too am a genius for correctly inserting my legs into my pants this morning." - candletears7 - TGP

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agoldoor
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Post by agoldoor »

G'damn you rule IV!

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Post by agoldoor »

Wow, and already verified by onthetundra! Everyone here works quickly! =)

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agoldoor
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Post by agoldoor »

Alright, I finally completed my build of this one... and I have to say, HOLY GOD!

This is EASILY the loudest pedal I've ever built or played. A lot of other pedals I've built or played that border on that edge of being the "MOST" of something end up also being on the verge of farting out, or completely falling apart (transistors completely gating with certain knob settings, high volume breaking out into squealing/oscillation, etc.)... but this certainly doesn't do that. I was unable to play around with this guy on anything more than 1.5 on my amp's volume knob. It's THAT GOD DAMNED LOUD.

Glad this one's been traced though finally, bravo to all involved.
:applause: :applause: :applause:

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