Earthquaker Devices - Ghost Echo  [traced]

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

Which 1m Resistor (ie: R?) needs to be swapped with a 470R?

I'm going to try this tonight and see if I get to unity

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nativetrash
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Post by nativetrash »

Nevermind - I saw r21 - i need to use my eyeballs as my wife always tells me

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Post by nativetrash »

And now I've freaking broken the brick somehow when de-soldering R21 - not sure if it's even worth trying this build again

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Motter
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Post by Motter »

If anyone wants to double check my resistor values from the other photos, here are the labelled components.

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Post by kodiakklub »

nativetrash wrote:And now I've freaking broken the brick somehow when de-soldering R21 - not sure if it's even worth trying this build again
DON'T GIVE UP!! i fear i may have fried my brick as well, but i will be buying a new one if i did.

@motter: i personally think the circuit was perfect except for the 1M/470 debacle. i will switch back the 10k/22k and hope that it works better than originally. i dont think theres anything more to fix on this circuit.

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Post by kodiakklub »

well i switched the 10k/22k back to the orig schem spec but replaced the 1M w/ a 470. its extremely close to unity gain now, but i ruined something(s) in the process. i know i tore up some pads and traces for the brick. hope i didnt fry the brick. its still only passing a clean uneffected signal bypassed or engaged. very odd. gonna etch another board and try again.

and i reccommend this regulator instead of the wimpy little TO92 one: http://www.taydaelectronics.com/lm7805- ... -1-5a.html
good for 1.5A! has a heatsink. should be bullet proof.

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kodiakklub
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Post by kodiakklub »

updated schemo:
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nativetrash
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Post by nativetrash »

So can we confirm that changing the resistor brought this back up to unity close enough that it would be worth purchasing another reverb brick and trying again?

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Post by kodiakklub »

absolutely. changing the 1M to 470R is damn near unity. i will be building another very soon myself.

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nativetrash
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Post by nativetrash »

Sweet! I'm going to etch another board & order another brick & give this a 2nd try

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Post by nativetrash »

I finally got my new reverb brick so I'm going to attempt to have this working tonight, fingers crossed!

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Post by nativetrash »

Now I've got a problem that's different - I just get a clicking when I turn the effect on - any idea what is wrong?

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Post by kodiakklub »

can you try a different 2399 chip? perhaps that is fried? have you metered the regulators to make sure they are putting out 5V?

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nativetrash
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Post by nativetrash »

I can try a different chip - I'm using the other reg chips with heat sink - is the flat side still the flat side in their orientation?

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nativetrash
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Post by nativetrash »

It's a constant click click click click

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Post by nativetrash »

I was an idiot and didn't socket my ICs this time around so I'm likely going to build this one last time from scratch & use the original regulators i used before & socket the ICs - luckily I desoldered my reverb brick without any problems this time

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Post by Govmnt_Lacky »

nativetrash wrote:I was an idiot and didn't socket my ICs this time around so I'm likely going to build this one last time from scratch & use the original regulators i used before & socket the ICs - luckily I desoldered my reverb brick without any problems this time
Recommend using ALL new parts (other than the brick of course)

New ICs, new regulators, socket everything! :applause:

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Post by nativetrash »

Rebuilt & socketed everything and the third time was indeed a charm! Works and sounds great.

Thanks to everyone who helped!

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Post by Motter »

Great job. Thanks for verifying, sorry about the initial mistakes in my trace.

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nativetrash
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Post by nativetrash »

I used it once to test and then after boxing up I get sound when the effect is engaged but no effect at all, just a slightly different sound of my bypass signal. I'm assuming that the chip perhaps fried from too much voltage? Any other ideas?

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