JHS Japan Fuzz Veroboard Verification

[andy-h-h]

The output cap goes from the junction of the 1k resistor and the 10k trimmer, to pin 3 of the volume pot.  You have one end of the output cap connected to -9v / in parallel with the 1k resistor. 

The 0.05u (50n) cap is in the right position according to the schematic (Across pin 3 and pin 2 volume). 

[ToneRangerAudio]

The down side of the 10nF, output cap, should go in Volume 3. You have to change a bit the layout to keep on the board the 0.50uF cap and connected on the Volume 2 and Volume 3... no so much easy, at my first sight (not impossible, of course).

Did you think of put that 0.50uF cap directly on the pot?

Okay! I moved the volume 1 connection down to the positive ground rail, and just moved the 10nF cap down to it as well. That took away a jumper and trace cut! For the sake of staying neat and orderly, I just decided to keep the bright cap on the board. Let me know if that looks right.

Top pic is the inline trimmer, bottom is the box trimmer with a little bit bigger board and slightly varied jumpers.

[Rob Strand]

I have a strong suspicion the schematic is wrong.

The 50nF cap should go between the collector of Q2 and pin 3 of the output pot.

As shown, if you connected it to a tube amp it's going to be putting 4.5V into the grid.  That's not going to be good.   I doubt JHS would do that.

[ToneRangerAudio]

I have a strong suspicion the schematic is wrong.

The 50nF cap should go between the collector of Q2 and pin 3 of the output pot.

As shown, if you connected it to a tube amp it's going to be putting 4.5V into the grid.  That's not going to be good.   I doubt JHS would do that.

The 50nF cap is a treble cap. Without it, the circuit is dark. You're right, there was no output cap in the schematic because it adds "chaos" as Josh said. Obviously, a little different thinking than most.

[Rob Strand]

The 50nF cap is a treble cap. Without it, the circuit is dark. You're right, there was no output cap in the schematic because it adds "chaos" as Josh said. Obviously, a little different thinking than most.

If that's how it's then that's how it is, so to speak.

It's going to create different chaos on amps with AC coupled inputs and DC coupled inputs - not consistent chaos  .

[ToneRangerAudio]

The 50nF cap is a treble cap. Without it, the circuit is dark. You're right, there was no output cap in the schematic because it adds "chaos" as Josh said. Obviously, a little different thinking than most.

If that's how it's then that's how it is, so to speak.

It's going to create different chaos on amps with AC coupled inputs and DC coupled inputs - not consistent chaos  .

Exactly. Grey Bench Electronics did a great video on it today explaining it with this exact circuit!

[Rob Strand]

Exactly. Grey Bench Electronics did a great video on it today explaining it with this exact circuit!

You are well in front of me on this one - I should be asking you the questions

[andy-h-h]

The down side of the 10nF, output cap, should go in Volume 3. You have to change a bit the layout to keep on the board the 0.50uF cap and connected on the Volume 2 and Volume 3... no so much easy, at my first sight (not impossible, of course).

Did you think of put that 0.50uF cap directly on the pot?

Okay! I moved the volume 1 connection down to the positive ground rail, and just moved the 10nF cap down to it as well. That took away a jumper and trace cut! For the sake of staying neat and orderly, I just decided to keep the bright cap on the board. Let me know if that looks right.

Top pic is the inline trimmer, bottom is the box trimmer with a little bit bigger board and slightly varied jumpers.

Hello - you still have the 10n cap in the wrong place.  Like this - here's a rough and ready vero with no voltage inverter / filtering / polarity protection.  You get the idea...

I had a quick play with this on LTspice.  You want something bigger than the standard 10n on a fuzz face to get close to the response of no cap at all (like the schematic).

Grey Bench Electronics has done a great job on YouTube breadboarding it, so I don't feel the need to test this myself.

[ToneRangerAudio]

The down side of the 10nF, output cap, should go in Volume 3. You have to change a bit the layout to keep on the board the 0.50uF cap and connected on the Volume 2 and Volume 3... no so much easy, at my first sight (not impossible, of course).

Did you think of put that 0.50uF cap directly on the pot?

Okay! I moved the volume 1 connection down to the positive ground rail, and just moved the 10nF cap down to it as well. That took away a jumper and trace cut! For the sake of staying neat and orderly, I just decided to keep the bright cap on the board. Let me know if that looks right.

Top pic is the inline trimmer, bottom is the box trimmer with a little bit bigger board and slightly varied jumpers.

Hello - you still have the 10n cap in the wrong place.  Like this - here's a rough and ready vero with no voltage inverter / filtering / polarity protection.  You get the idea...

I had a quick play with this on LTspice.  You want something bigger than the standard 10n on a fuzz face to get close to the response of no cap at all (like the schematic).

Grey Bench Electronics has done a great job on YouTube breadboarding it, so I don't feel the need to test this myself.

You're right. I don't know why I keep making that mistake. The cap should come from out of the trimmer before volume 3.

[andy-h-h]

So close - missing a cut under the output cap.   

[ToneRangerAudio]

So close - missing a cut under the output cap.   

Moved some stuff around to make room for the transistor sockets. I'll label those here in a bit. I think this is looking good!

[andy-h-h]

That'll work - you got there in the end.   

[ToneRangerAudio]

That'll work - you got there in the end.   

Finally haha. Appreciate your help!

[mzy12]

I have a question - you don't have a bypass cap going directly from +9v to ground. I know you're immediately turning it into -9V with the IC, but I presumed it would be good practice to add even, say, a 47uf cap across 9V, no?

[andy-h-h]

That'll work - you got there in the end.   

Finally haha. Appreciate your help!

Actually    I missed something as I was too busy looking at the output cap.  The 10uf on the inverter should be across pins 2 & 4. 

[ToneRangerAudio]

Boom.