Pete Cornish - NG-2

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andy-h-h
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Post by andy-h-h »

Should look something like this. It is possible to trim this down a couple of rows too if you want to move a few things around, and the 100uf cap is optional, as is the power diode, as you could just take power from the Cornish Buffer layout that IvIark has nicely provided on guitar effects layouts.

And this is just a work-a-like based on the Nugget Fuzz. No claims that this is a real NG-3.
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sopapo1
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Post by sopapo1 »

I just realized that in the old pic ungooped of a cornish ng in the first page (more that ten years ago¡¡¡ :lol: :lol: ) there is a third board with an ic in it instead of the usual buffer+effect ¿¿?? what is? also, very surprised of the perf... :hmmm: the blue capacitor and the resistor is maybe something related to reject RF or protection for shocks???

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andy-h-h
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Post by andy-h-h »

I've seen that pic too. The third board with the IC might be another buffer, or possibly even a power inverter to run PNP transistors. I think a buffer is way more likely, but you never know....

The blue cap is a link to ground. You can find more details on this by looking at the G2 schematic, as it included in the jack wiring. I read somewhere this helps with noise filtering / interference.

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Post by palelight »

andy-h-h wrote:I've seen that pic too. The third board with the IC might be another buffer, or possibly even a power inverter to run PNP transistors. I think a buffer is way more likely, but you never know....

The blue cap is a link to ground. You can find more details on this by looking at the G2 schematic, as it included in the jack wiring. I read somewhere this helps with noise filtering / interference.

There's a few pics of very early NG fuzzes floating around (gooped and non-gooped), both with the IC and perf daughterboards. By later versions (the standard grey series), the ic and daughterboard are gone. I'm more inclined to believe it was a power inverter, I think some early examples were definitely sporting some PNP transistors (pure speculation based on the transistor casing). Later NG's sport pretty standard TO92 transistors (assume BC549 or similar), likely doing away with the need for a power inverter. Pete's pedals are usually laid out very practically from a design standpoint (if not space conscientiously). The buffer is directly adjacent to the input for example, the fact the ic board was directly in front of the power plug makes me think it was related to that. Again, just a guess.

I've never seen a Pete C pedal use an opamp buffer, P2/G2/SS2 etc. all use the standard bootstrapped fet buffer, going well back into examples from the early 90's (the Guild Brian May Box etc.). But you never know I suppose.

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andy-h-h
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Post by andy-h-h »

palelight wrote:
I've never seen a Pete C pedal use an opamp buffer, P2/G2/SS2 etc. all use the standard bootstrapped fet buffer, going well back into examples from the early 90's (the Guild Brian May Box etc.). But you never know I suppose.
That's a very good point. I might have to try building a PNP version now.

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Post by andy-h-h »

andy-h-h wrote:Should look something like this. It is possible to trim this down a couple of rows too if you want to move a few things around, and the 100uf cap is optional, as is the power diode, as you could just take power from the Cornish Buffer layout that IvIark has nicely provided on guitar effects layouts.

And this is just a work-a-like based on the Nugget Fuzz. No claims that this is a real NG-3.
Sorry - just realised there's an error on the layout I posted. :oops: the 100k resistor sitting on G29 should go to J29 (if anyone has even used the layout) the 330ohm resistor sitting next to it should be 360ohm, but that's no biggie.

Side note: if you want more output, try moving the 100n captor to the collector of Q5.

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