Adding Lfo to uglyface. PLEASE HELP!!!!

[brokenstarguitar]

I have the Musicpcb.com uglyface pcb without the lfo ( http://www.musicpcb.com/pcbs/acln72o2xgsnj8pfqkokmpx0ts5g1g ) and i just build the P-LFO from Grindcustoms.com ( http://www.grindcustomsfx.com/forum/viewtopic.php?f=2&t=391 ) but im having an issue putting the 2 together. Anyone know how to achieve this? If im correct the only way to hook them is into the vactrol on the P-LFO but that doesnt make sense to me. Can anyone help me with this?

[GibsonGM]

You need DUCK ARSE to come in and "decode" for you!  He has built many variations of this and I bet could tell you how to do it.  It would take a little work because you will need to understand the uglyface PCB enough to move some stuff.  Are you up for that?

[duck_arse]

someone call? ahh, I should really get back to finishing those mods on my first ever ugly face. distracted by - what's that over there?

one way to do is to string the ldr in the lfo board between pin 5 of 7555 and either ground or V+. you might be able to use that, but it's a rough hack at best.

otherwise, the EASIEST way I can see at this late hour, switching betweeen 3 and 4 different pages of things, is to add a switch (spdt) between pin 3 7555 and the original "optldr", and "L1" of the "VACT_1B" of the grindcustom. connect "L2" of VACT_1B to pin 2 7555.

bob's yer unkle. good luck.

[GibsonGM]

I knew you'd come give some aid, DA!  Good call; I for the life of me can never seem to figure out how some things work. The UglyFace is 'off the beaten path' of my normal builds....one day I WILL put it together, I promise you that! 

[brokenstarguitar]

Ok, let me get this correct.
Pin 3 of the 7555 to lug 1 of the spdt,
the "optled" on the uglyface (either side) to lug 2 of the spdt, then "L1" from the grindcustoms "optled" to lug 3 of the spdt. Then "L2" from the GCs "optled" to pin 2 of the 7555 to complete the circuit. Is that correct Duck Arse?

someone call? ahh, I should really get back to finishing those mods on my first ever ugly face. distracted by - what's that over there?

one way to do is to string the ldr in the lfo board between pin 5 of 7555 and either ground or V+. you might be able to use that, but it's a rough hack at best.

otherwise, the EASIEST way I can see at this late hour, switching betweeen 3 and 4 different pages of things, is to add a switch (spdt) between pin 3 7555 and the original "optldr", and "L1" of the "VACT_1B" of the grindcustom. connect "L2" of VACT_1B to pin 2 7555.

bob's yer unkle. good luck.

[duck_arse]

erm. like I allays says, draw the circuit. never mind.

the pin 3 of 7555 to the COMMON of your switch. one end of one ldr to the switch N/C, one end the other ldr to the switch N/O (don't number the pins - it is meaningless). the other end of both ldr's to pin2 7555.

this above is one way. with the circuit drawn (again), more connection options/methods become clear.

if you roll-yr-own vactrol, you can put a single ldr (wire as per standard face) in with two leds, one from the 386 output and one from the lfo. THEN, you can either set their mod levels via their bright pots, or switch between one/the other/neither/both. etc.

....one day I WILL put it together......

me too, gibson.

[brokenstarguitar]

erm. like I allays says, draw the circuit. never mind.

the pin 3 of 7555 to the COMMON of your switch. one end of one ldr to the switch N/C, one end the other ldr to the switch N/O (don't number the pins - it is meaningless). the other end of both ldr's to pin2 7555.

this above is one way. with the circuit drawn (again), more connection options/methods become clear.

if you roll-yr-own vactrol, you can put a single ldr (wire as per
standard face) in with two leds, one from the 386 output and one from the lfo. THEN, you can either set their mod levels via their bright pots, or switch between one/the other/neither/both. etc.

....one day I WILL put it together......

me too, gibson.

What does N/C and N/O mean? Sorry for my ignorance. Im just learning.

[bluebunny]

Normally-closed or normally-open.  Duck is referring to one side of the switch or the other.

[duck_arse]

when you draw the switch, one of the other lugs (your drawing, your choice) contacts the common connection. this is called the normally closed contact. the (drawn as) open contact is called the normally open contact. this means you don't need any 1-2-3 numberings to get confused with.

any spring return switches will have the n/o and n/c contacts marked. common will also be marked sometimes.

[brokenstarguitar]

I did everything u said to do but the 7555 got super hot. Burnt my finger actually. It sound ok at first then there was a huge volume drop.. im pretty sure i blew the 7555. Plus, it there a reason im not getting the weird sounds from the uglyface? I have just the UF hooked up, idk whats going on with it.

[duck_arse]

I did everything u said to do

well there's the problem.

can you draw me a schematic (of some description) of what you've done? if the 7555 was ok and the uglyface was working, correctly adding another ldr to the circuit won't get it hot or bothered.

[telebiker]

Thinking of building the circuit from the same PCB. LFO would be nice addition here.

Just curious, has anyone succeeded in adding LFO to the musicpcb.com circuit? Probably, someone has schematics for this?

[BetterOffShred]

I resurrected an old thread about this device just recently that contains most of the known schematics for the LFO version as well as some mod discussion.   I ended up removing some of the mods from the LFO version after A/B them.  Also, there's a blend mod to mix between straight 386 distortion and the 555 side of the effect.  Very fun.

Look for that other thread.. in the last few weeks. 
www.diystompboxes.com/smfforum/index.php?topic=70747.40

There

[telebiker]

I resurrected an old thread about this device just recently that contains most of the known schematics for the LFO version as well as some mod discussion.   I ended up removing some of the mods from the LFO version after A/B them.  Also, there's a blend mod to mix between straight 386 distortion and the 555 side of the effect.  Very fun.

Look for that other thread.. in the last few weeks. 
www.diystompboxes.com/smfforum/index.php?topic=70747.40

There

Thanks for the link. I believe you're talking about this post in "Uglyface with LFO --new vero-- (unverified)" thread which you've sent? https://www.diystompboxes.com/smfforum/index.php?topic=70747.msg1135215#msg1135215

It has Munky's post with the schematics: https://postimg.cc/hJV9qXjW

However, not sure how to add this to musicpcb.com pcb: http://www.musicpcb.com/pcbs/acln72o2xgsnj8pfqkokmpx0ts5g1g

Also, found "escobedo's ugly face video demo" old thread which has rankot's trace: https://www.diystompboxes.com/smfforum/index.php?topic=91484.msg1052902#msg1052902 Still not sure how to fit it all together.

[BetterOffShred]

The schematic of just the LFO shows you the "injection points"   I'd definitely up the 22uf to 100uf, though I likes the 250k pot without the 22k resistor in parallel better on my build.  And I think I went with the 22k instead of the 56k that is changed on the LFO layout. 

Page 3 and 4 have all the layouts and schematics. 

I'd build the LFO on a piece of stripboard and then hook it up piggyback to the pcb locations. 

It's also worth mentioning i was unable to get the LFO working unless I used a 358 chip.. the 4558 didn't work for me. They may be Chinese copies or something but they work in overdrive and stuff..   

[telebiker]

Hello!

I'm also building an Uglyface using musicpcb plate and would like to add LFO there. I would be really grateful if someone could give some ideas what can be wrong with my build. But I'm stuck and don't understand why the LFO is not working.

The interesting thing is that I've done LFO part twice and each time it didn't work. However, LFO was working on my 1st attempt for several minutes. Suddenly it stopped, but I can't figure out what changed.

What can be wrong? What should I check firstly? I'm not sure how to debug this and if audioprobe helps here. If some photos are required I can attach them.

[duck_arse]

you know the rules, telebiker, stump up those photos. and voltage measures, too, please. and the circuit diagram you are working from.

[telebiker]

you know the rules, telebiker, stump up those photos. and voltage measures, too, please. and the circuit diagram you are working from.

I'm using a musicpcb.com plate and trying to add LFO according to that diagram:



Since sensivity pot already exists on musicpcb pcb, I used injection points like this (I have also omitted C3 cap as it was advised on madbean forums, not sure if it is allowed to share the links here):



I have the following voltages:
1. Sensivity pot point; LFO on: regularly varies 3.2–5V (that's a sign that LFO works)
2. Sensivity pot point; LFO off: static 5.5V (that's expected I believe)
3. 386 Pin 5 point; LFO on: very slightly varies randomly around 5.632V
4. 386 Pin 5 point; LFO off: very slightly varies randomly around 5.602V

I cannot hear any LFO on wet signal for some reason. The curious thing is that LFO worked for some time once I have built the circuit, but then it stopped and I can't figure out what changed.

Not sure that photos will help somehow, but attaching them just in case.






Would be grateful for any ideas what can be wrong there.

[telebiker]

Since sensivity pot already exists on musicpcb pcb, I used injection points like this (I have also omitted C3 cap as it was advised on madbean forums, not sure if it is allowed to share the links here):



I have the following voltages:
1. Sensivity pot point; LFO on: regularly varies 3.2–5V (that's a sign that LFO works)
2. Sensivity pot point; LFO off: static 5.5V (that's expected I believe)
3. 386 Pin 5 point; LFO on: very slightly varies randomly around 5.632V
4. 386 Pin 5 point; LFO off: very slightly varies randomly around 5.602V

I cannot hear any LFO on wet signal for some reason. The curious thing is that LFO worked for some time once I have built the circuit, but then it stopped and I can't figure out what changed.

Does this layout to add LFO make sense at all?