Hi everyone,
Some background:
I'm starting a new project, retrofitting a V1 Triangle big muff circuit into an old EHX enclosure, using a Ram's head replica PCB. Here is the circuit I want to go with:
![Click image for larger version
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I managed to get my hands on 4 original FS37000 PNP transistors (PNP version of the NPN FS36999), pulled from a 1970s EHX pedal.
My question:
If I want to use those transistors while staying true to the circuit above, would it be enough to change the power supply polarity and double-check the transistor pin-out, or is it necessary to change the resistor values as well, to adjust biasing? There are no polarised capacitors in the circuit.
I found a Triangle circuit with PNP transistors and very different resistor values, but I'm not sure if they differ to account for the PNP design, or if they are just oddball values:
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I did see some examples of Ram's head circuits with either PNP or NPN transistors, but very similar resistor values (on this page: http://www.bigmuffpage.com/Big_Muff_...ics_part2.html), which might suggest that the resistor values don't have to be adjusted?
Some background:
I'm starting a new project, retrofitting a V1 Triangle big muff circuit into an old EHX enclosure, using a Ram's head replica PCB. Here is the circuit I want to go with:
I managed to get my hands on 4 original FS37000 PNP transistors (PNP version of the NPN FS36999), pulled from a 1970s EHX pedal.
My question:
If I want to use those transistors while staying true to the circuit above, would it be enough to change the power supply polarity and double-check the transistor pin-out, or is it necessary to change the resistor values as well, to adjust biasing? There are no polarised capacitors in the circuit.
I found a Triangle circuit with PNP transistors and very different resistor values, but I'm not sure if they differ to account for the PNP design, or if they are just oddball values:
I did see some examples of Ram's head circuits with either PNP or NPN transistors, but very similar resistor values (on this page: http://www.bigmuffpage.com/Big_Muff_...ics_part2.html), which might suggest that the resistor values don't have to be adjusted?
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