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Friday, March 31, 2017

Sunn Buzz SB-1G

Saw this one over on the Tagboard blog and thought I'd give it a go for Fuzz Friday. It's a silicon variation of the Maestro FZ-1. Originals use a single AA battery (1.5v), so I've included 2 voltage diving resistors to drop the the normal 9v supply down to 1.5v. (The yellow trace in the PCB side indicates the 1.5v rail.) Originals used 2N2923 transistors, but I would imagine other low gain transistors will work (hFE range on the 2923 is 90-180). Just mind the BCE pinout. Here's the schematic for reference.


8 comments:

  1. Built it. Didn't work. I replaced the 100k and 20k divide with a 10k and a red LED, with a 100uF cap across the LED and it worked. I've got outrageously high hFE transistors (~300) for this circuit, so lower gain might not require my change to the power supply.

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    1. Hello Ryan, does it mean that you replaced the 100k with a 10k and the 20k with a red led, with a 100uF cap across this LED? My transistors, as I explain in the post below are 2923 (hFE-140)... Thanks. Reno.

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    2. Yes, exactly. The LED will drop a consistent 1.2 to 1.5 volts and is a much stiffer voltage source than just a resistor divider. Basically it's just functioning as a cheap zener diode

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    5. The capacitor should be in parallel with the LED, and the negative side should go to ground.

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    6. It works very well, the buzz sound is a little bit more dirty, less compressed, but the color is here and the pedal works fine with a good volume and no noise. Thanks Ryan for your help.

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  2. Built it but doesn't work (except led and bypass...yeah). It is one of my firsts built and I am not very experimented in electronics, I am trying to understand what I am doing but it's not won.
    My transistors are 2N2923 ECB, I tested its with a cheap components tester, so it seems that the ECB symbol letters are the same as the circuit drawing ( however the transistors symbols are inverted with the straight line at the opposite).
    I used the general layouts notes, as for my first built which was a succès, I checked everything I could and I am now looking for a little help from someone who would like to help me to find the solution. Thank's a lot

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