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Hi everyone,

Was just going over the schematic for the VFE Triumvirate and noticed that the diode clipping section in the treble part of the circuit has a link joining all four diodes (cathodes of D3 and D5 + anodes of D4 and D6).  Not sure I've seen this arrangement before and wondered if someone could provide a little explanation of the pros/cons of the "jumper"?

- brad -

I actually just talked to Peter yesterday. Looks like I'll have a new batch of MCU very soon so I can resume sales of the existing VFE projects.

Thanks Brian.  I really appreciate the update and look forward to purchasing the Triumvirate kit as soon as it's available.

Just a quick note to ask if and when the VFE Triumvirate PCB might be back in stock.  I asked Brian a similar question by email but thought I'd post here as well as per his suggestions on sharing the Q's and A's with all forum members.

I'd also be interested in buying from any forum members how might have a spare Triumvirate kit they aren't planning to get to...

Thanks,

- brad -

IT'S ALIVE!!!

One of the resistor's pads was a little suspect so I soldered in a jumper to the next component...just to make sure...but, aside from that everything is sounding great.  I'm going to put it up against my rehoused Danelectro French Toast later today but, on its own, it's a pretty excellent fuzz.

Are these inkjet or laser prints on the waterslide decals?  Just curious to know if the Pledge reacts with the ink.  Am I safe in assuming you'd still have to do mist coats over inkjet?

Well, I measured resistors, I checked and re-checked orientations and potential solder bridges, I poked and I probed and I almost packed it in for the night.

By pure dumb luck, I decided to touch R6 with my iron where it looked like I had an extra blob of solder on the leg and something moved around like a piece of debris...turned out it was part of the resistor's leg - it was broken off right at the mass of the resistor!  I replaced it with a new 100k, re-tested the voltages and everything looks MUCH better (my Q3 collector is now closer to 6.8 rather than GGG's 7.28 but everything else is nice and close).

I didn't get to REALLY fire it up since it's about midnight and I live in a townhouse but I'm looking forward to test driving it tomorrow!

Thanks for the feedback...it helped me zero in on those R2-R9 resistors!

OK.  I'll see what I can do for a photo.  In the meantime, I'll investigate those resistors (I did check that the colour codes match what they are supposed to be but didn't measure or test to see if they might be bridged somewhere they're not supposed to go).  I'm also set to go in with the audio probe to see where the signal might get messed up.

Could the caps around Q1 and Q2 be suspect as well (given the voltages I've measured)?  How about those "shorted" D3 and D4 diodes (keeping in mind that I measured them IN THE CIRCUIT)?

Hi folks!

Troubleshooting my build...I've got very little output and it's clean (not distorted at all).  I've noticed that D3 and D4 are "shorted" (i.e. same voltage measured in same direction) but I'm not sure if that's an issue in this circuit.  I have also measured the following voltages so I'm hoping someone can point me in the direction of the most likely culprit(s).

Voltages:

Supply at board = 9.14

Q1:
C = 5.38 (General Guitar Gadgets (GGG) calls for 2.20)
B = 0.00 (GGG calls for 0.73)
E = 0.00 (GGG calls for 0.16)

Q2
C = 4.77 (GGG calls for 7.50)
B = 5.38 (GGG calls for 2.20)
E = 4.74 (GGG calls for 1.60)

Q3
C = 6.94 (GGG calls for 7.28)
B = 0.83 (GGG calls for 0.78)
E = 0.21 (GGG calls for 0.22)

Q4
C = 7.53 (GGG calls for 7.63)
B = 0.82 (GGG calls for 0.84)
E = 0.24 (GGG calls for 0.26)

Any help would be much appreciated!

Yes...my first 3PDT switch basically chooses or bypasses the "loop" section of the pedal and then the switch shown in my diagram chooses between Loop 1 and Loop 2.  Not having a 4PDT switch at the time, I chose NOT to ground the Loop inputs because, in my mind, doing so would put the 9V power from the LED indicators onto the signal path?  My assumption the wiser move is to replace the 3PDT with a 4PDT, no?

Reposting a 3PDT wiring question that I shared with the "DIY Stompboxes" Facebook page: I've built a 2 loop switcher using a 3PDT switch with a second 3PDT that bypasses the two loops. I have noticed that the NON-selected loop tends to bleed a little signal onto the selected loop and I'm pretty sure that this is because the inputs are NOT grounded (I know this can be an issue but still don't fully understand given the concept of "true bypass") so my question is this: can I ground the inputs on the LED indicator poles of the 3PDT as shown by the dotted lines in my photo without issue or is a 4PDT switch a MUST in this scenario?

Thanks for the confirmation...and the soldering tip.  I was just thinking that keeping the LED connections on the PCB and using a wire connection to the 3pdt switch would help tidy up my usual rat's nest of wires and bare leads!

Is this something I should have posted in "General Questions" rather than here in "Beginner's Paradise"?

Hi everyone!

I'm planning to begin work on a couple of Madbean Wigl boards and I had a quick question about the two "indicator" LEDs:

If I only want to use a SINGLE indicator LED and I want to have it flash in time with the rate setting, can I omit "LED1" completely and then run the "LED2" cathode to the "-" trace for "LED1" instead of the "LED2" cathode trace (hopefully my point is a LOT clearer than my words appear to make it!!!)?

Thanks,

- brad -

Thanks for the quick reply.

In my mind I was ordering the "s" version of the ICL7660 from Tayda and didn't realize I actually pulled the trigger on the TC1044SCPA until it arrived (yet another one of my many brain cramp moments!).

This is going into the Tayda Plexitone kit (similar to the Boneyard if I'm not mistaken) which has some known oscillation issues.

I power my pedal collection with a Godlyke "power-all" and I don't have any other charge pumps before or after this one.

I have minimized the whine/whistle by changing the orientation of a few wires inside the build and have tried some cheap eBay ICL7660S ICs but I don't have 100% confidence in those.  Hopefully the TC1044SCPA might elliminate the issue altogether!

- brad -

I'm working on a project with a charge pump and have run into the dreaded oscillation/whine of the ICL7660.  I have used both the "C" and "S" variants without any luck in removing the noise.

I happen to have a few TC1044SCPA's in my collection and see that a fellow on another forum used one successfully in his build so I am curious to know if anyone confirm that the TC1044SCPA is an acceptable alternative for the ICL7660S (the spec's appear to be similar but I am quite new to reading those things!)?

Any help would be MUCH appreciated!


- brad -