MODIFICATION The FZ-1 - CB style

I’ve had a FZ-1 breadboarded for over a year now, and I have yet to find transistors that make it work right. Every few months I get a new batch, and I’m still searching. Maybe I’ll start looking for NPN…
The leakage is critical to getting the trannys to bias correctly.
Are you running a 1.5V or 3V rail? I've tried it at 9V and did not like the tone.
 
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The leakage is critical to getting the trannys to bias correctly.
Are you running a 1.5V or 3V rail? I've tried it at 9V and did not like the tone.

I went with the Mister Fuzz schematic, so it’s 9 down to 3v. I’ve gotten pretty close, but not close enough to make it permanent. I had the same issue with my MKI build. Part of the fun, I suppose…
 
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I went with the Mister Fuzz schematic, so it’s 9 down to 3v. I’ve gotten pretty close, but not close enough to make it permanent. I had the same issue with my MKI build. Part of the fun, I suppose…

You can tweak R7 to dial-in Q2, R8 and/or R9 to dial-in Q3. Even with the resistor tweaking, not every transistor will work well for Q2 and Q3. Bear in mind that the ATTACK pot varies Q2's bias, so adjust R7 to get the best range on the ATTACK pot.

As a point of reference, on mine Q2-C runs from 3.00V (ATTACK min) to 1.77V (ATTACK max). Q3-C runs at 1.97V. Vcc = 3.07V.

BTW, I only tried the circuit from post #14 on the breadboard. My pedal uses the schematic from post #1.
 
Oh sorry....I was reading the thread and saw your post I quoted. It made me think of the Servo FF (Mechanic)...no connection to @Coda 's post. I'll just leave now, so the grownups can talk.

I was referring to the Servo Fuzz Face as well, since my FZ1 is stuck in the in-between…
 
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You can tweak R7 to dial-in Q2, R8 and/or R9 to dial-in Q3. Even with the resistor tweaking, not every transistor will work well for Q2 and Q3. Bear in mind that the ATTACK pot varies Q2's bias, so adjust R7 to get the best range on the ATTACK pot.

As a point of reference, on mine Q2-C runs from 3.00V (ATTACK min) to 1.77V (ATTACK max). Q3-C runs at 1.97V. Vcc = 3.07V.

BTW, I only tried the circuit from post #14 on the breadboard. My pedal uses the schematic from post #1.

I’ll have to get back on it and start with some new measurements. It got to the point that whenever I got a new batch of transistors I would try a few. Like I said, maybe I’m being too picky and should just commit to something that’s close enough.
 
You can tweak R7 to dial-in Q2, R8 and/or R9 to dial-in Q3. Even with the resistor tweaking, not every transistor will work well for Q2 and Q3. Bear in mind that the ATTACK pot varies Q2's bias, so adjust R7 to get the best range on the ATTACK pot.

As a point of reference, on mine Q2-C runs from 3.00V (ATTACK min) to 1.77V (ATTACK max). Q3-C runs at 1.97V. Vcc = 3.07V.

BTW, I only tried the circuit from post #14 on the breadboard. My pedal uses the schematic from post #1.

I dug my breadboard FZ-1 out. Right now I get the following voltages: Q2= 3.2 (min) 2.9 (max), Q3= .39. VCC is 3.2v.
 
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Q2 is hardly changing when you rotate ATTACK, that ain't right. Referring to the Mr. Fuzz schematic, make sure R5 and R6 are correct. Have you measured the HFE and lkg of Q2? You could try reducing R6 or increasing R7 (try R7 first).

Q3 is running way too hot (collector current too high). Your choices are:
1. Find a transistor with lower leakage
2. Reduce R9.
3. Reduce R8.

I'd try them in that order.

Are you sure your breadboard is built correctly?
 
Well, I did it. I have successfully breadboarded an accurate-sounding FZ-1. A serious bucket-list accomplishment. I read through this thread for the 20th time, pulled out a fresh breadboard, and got to work. I had to audition about 4000 different resistor values. The trick ended up being the "new" R10. Before that addition I wasnt getting anything near .7 on Q3...I was measuring like 0.035! Now everything works. Q1 is a 5457 cause it was handy (I tried to say that in my most Chuck Bones voice). It sounds very buzzy. I built mine stock...I reverse-engineered your tone section out of there. I may add it back, though. Thanks for this thread. Any chance we can get your Vero layout? I suppose I could make my own, of course...
 
Sorry, I know this isn't the point of this thread at all, but at the end of your first post on your note about PNP vs NPN transistors, you mention using a negative ground for PNP and how, for example, the Way Huge conquistador just turned the circuit, "upside down." Would I be correct in assuming this just means swapping where the 9V and ground connections normally go on the board?
 
No.

I don't know what you do or don't know about electronics, so I won't get into a long discussion here. Study the Conquistador schematic and that should clarify things.
 
Sorry, I know this isn't the point of this thread at all, but at the end of your first post on your note about PNP vs NPN transistors, you mention using a negative ground for PNP and how, for example, the Way Huge conquistador just turned the circuit, "upside down." Would I be correct in assuming this just means swapping where the 9V and ground connections normally go on the board?
You need some sort of understanding of how stuff flows. A good starting place would be here:
 
The Mizuque.com article provides a good discussion of running PNP transistors with a negative ground. Three comments:
  1. The article has the 2.2uF cap backwards on both schematics. Not that it matters much because the DC voltage across the cap <1V.
  2. The 20uF cap can connect to GND in both schematics. It does not have to connect to the positive rail in the PNP circuit.
  3. Power supply bypassing is always a good idea*. We should not depend on the impedance of the battery or power supply to ensure that the power supply rail has a low-impedance path to GND.
For another example of running a PNP Fuzz Face with a negative ground, check out the Fuzz Factory.

* Unless you're building a Fuzz Factory.
 
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Thanks for the information. I'm trying to put together an understanding of how this stuff works one step at a time haha. It's fairly clear to me now what is meant by, "turning the circuit upside down." (y)
 
Power supply bypassing is always a good idea*. We should not depend on the impedance of the battery or power supply to ensure that the power supply rail has a low-impedance path to GND.

* Unless you're building a Fuzz Factory.
Just out of morbid curiosity, why is this? I know the same is said about Devi Ever's Hyperion 2 with the oscillation control. I've seen some claims about how the circuit is required to be 'unstable' or whatever, but unfortunately for my inquisitive mind, this just isn't a good enough answer for me 😂

There's also a 47uf bypass cap in the PedalPCB schematics for the fuzz factory, will this produce an undesirable effect on the stability control?
 
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