Sun face clone signal delayed when engaged

[harrisxr650]

Hi people,

i've build this sun face from tagboardeffects

https://tagboardeffects.blogspot.com/2013/03/analogman-sunface-nkt275.html?lr=1

and added this voltage inverter again from tagboardeffects

http://tagboardeffects.blogspot.com/2012/05/negative-voltage-inverter.html

I used a matched AC128 set instead of NKT275,
while the fuzz sounds terrific it takes about one second, once i press the 3pdt, for the signal to be heard. when i press again to bypass the signal it does it as it with no problem.
replaced the 3pdt with a new one with no luck.

Everything else is working as it should be

Any ideas on where i should start looking?

BR

[antonis]

Try to reduce 47μF cap value..
(in the risk of ripple increace..)

[Rob Strand]

From what I can see there's no ground path for the 1uF input cap.
Try adding a 1M to 2M2 resistor from the audio input of the PCB to ground.
(Keep the 47uF cap.)

[harrisxr650]

From what I can see there's no ground path for the 1uF input cap.
Try adding a 1M to 2M2 resistor from the audio input of the PCB to ground.
(Keep the 47uF cap.)

Hi Rob,
I was just checking with PedalPcb.com and pcb guitar mania and both have a 2m2 res from from input to ground.
Gonna solder  sockets later on today and see how it goes.
thanks

Try to reduce 47μF cap value..
(in the risk of ripple increace..)

Gonna try this as well. thanks

[antonis]

(Keep the 47uF cap.)

IMHO, that cap is the only obvious reason for powering delay..

[Rob Strand]

(Keep the 47uF cap.)

IMHO, that cap is the only obvious reason for powering delay..

The charge pump is always powered.  As soon as you plug in the jack the charge pump is active and it should charge-up the output cap very quickly.  There's nothing linking the time you press the footswitch to when the unit is powered up.   That's what made me think it can't be the power.

For me the key point is the delay is always on the *first* activation of the footswitch.   That's a very common problem when there's no "de-pop" resistor in the input (or output) caps.  Normally you just get a pop on the first activation.  The input cap is discharged, and then charges when the footswitch is first pressed but after that it stays charged (for a long time).

The long delay doesn't make 100% sense to me but whatever the issue is it's going to be related to the input cap.

[ElectricDruid]

Accidentally fitted 100u in place of 1u for input cap?

[antonis]

Accidentally fitted 100u in place of 1u for input cap?

I was just about to say that 1μF cap with 25k (half value of trimmer pot) only needs 100ms (4 x time constant) to charge up to its nominal voltage level..
(the higher the pot setting the lower the charging time..)

[harrisxr650]

From what I can see there's no ground path for the 1uF input cap.
Try adding a 1M to 2M2 resistor from the audio input of the PCB to ground.
(Keep the 47uF cap.)

Ok.. added the pulldown res. with no luck

Try to reduce 47μF cap value..
(in the risk of ripple increace..)

Gonna try to swap with a 33uf and see how it goes, just a question though if the problem lies within the voltage inverter would the led delayed to light up as well?
BR
Harris

[antonis]

if the problem lies within the voltage inverter would the led delayed to light up as well?

No, in case of LED connected to +9V supply..
(which is reasonable for -9V loading prevention..)

[Rob Strand]

It doesn't make sense the converter is the cause of the delay.

I wouldn't hurt to check over both PCBs by eye to see if you have all
the leads going to the correct holes, all the links in and all the
cuts/holes drilled.

I would recheck the fuzz board still does not have this issue when powered from battery:
- disconnect the converter -9V from the pedal board
- power the *pedal* circuit with a battery connected to battery - to -9V and battery+ to gnd.

You never know, maybe it does!

This schematic shows the general wiring of the converter to the pedal pcb.
But it doesn't show the footswitch.  The two connections to the LED look
a but odd.
https://guitarpcb.com/wp-content/uploads/2018/10/PUFF_v4.pdf

Beyond that, some pics of you PCB would help.

Do you have a multimeter?

What you can do is measure voltages in the circuit, then press the footswitch
and see if those voltages glitch for a second.   For example measure the -9V
rail and the collector voltage on second transistor (Q2).

[antonis]

The two connections to the LED look a but odd.
https://guitarpcb.com/wp-content/uploads/2018/10/PUFF_v4.pdf

Ideed..
Taking in mind conventional 3PDT switch lugs numbering, No 5 is the middle lug of 4,5 & 6 column so LED should be always ON..

[harrisxr650]

Accidentally fitted 100u in place of 1u for input cap?

nope. checked to be sure, its  1uf

Accidentally fitted 100u in place of 1u for input cap?

I was just about to say that 1μF cap with 25k (half value of trimmer pot) only needs 100ms (4 x time constant) to charge up to its nominal voltage level..
(the higher the pot setting the lower the charging time..)

i'have replaced the trim pot with a 50k external pot if this has something to do

[harrisxr650]

And i forgot...... i didnt used the icl7660S,

I had some tc1044s around...

[harrisxr650]

From what I can see there's no ground path for the 1uF input cap.
Try adding a 1M to 2M2 resistor from the audio input of the PCB to ground.
(Keep the 47uF cap.)

Ok.. added the pulldown res. with no luck

Try to reduce 47μF cap value..
(in the risk of ripple increace..)

Gonna try to swap with a 33uf and see how it goes, just a question though if the problem lies within the voltage inverter would the led delayed to light up as well?
BR
Harris

Ok.. changed the 47uf with a 33uf. I even went to 10uf. With no luck.

Rebuild both circuits.. Same delay engaging the pedal.....

[harrisxr650]

It doesn't make sense the converter is the cause of the delay.

I wouldn't hurt to check over both PCBs by eye to see if you have all
the leads going to the correct holes, all the links in and all the
cuts/holes drilled.

I would recheck the fuzz board still does not have this issue when powered from battery:
- disconnect the converter -9V from the pedal board
- power the *pedal* circuit with a battery connected to battery - to -9V and battery+ to gnd.

You never know, maybe it does!

This schematic shows the general wiring of the converter to the pedal pcb.
But it doesn't show the footswitch.  The two connections to the LED look
a but odd.
https://guitarpcb.com/wp-content/uploads/2018/10/PUFF_v4.pdf

Beyond that, some pics of you PCB would help.

Do you have a multimeter?

What you can do is measure voltages in the circuit, then press the footswitch
and see if those voltages glitch for a second.   For example measure the -9V
rail and the collector voltage on second transistor (Q2).

checked again for wrong leads cuts etc. everything is fine..

Measured the -9v rail with the collector of Q2 and when off and its -9v ( checked the rail on the inverter as well and its -9.43v), once i turn on the effect it drops to -8v ( in Q2 collector) and then slowly rises to -8.77v and stays there.

[antonis]

Check 22μF cap and 470R resistor for correct values..

[harrisxr650]

Check 22μF cap and 470R resistor for correct values..

done! both are correct.

also the pics posted is the 2nd build, i check along the old one and got the same findings.

[antonis]

Is 2nd build made of 1st one parts..??
(if so, replace 1μF and 22μF caps..)

[harrisxr650]

Is 2nd build made of 1st one parts..??
(if so, replace 1μF and 22μF caps..)

Nope. Brand new everything and checked one by one for functionality and correct values .