@brd
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Thanks for the tip, I wish I had that information a few years ago. However, talent and patience are the missing ingredients here. Below is a photo of my first and last pedals, clearly showing no improvement in my art or my ADHD.
Big O
I have been around this forum for a while, long enough to know you are one of the most prolific build posters here. Your graphics and finish are second to none. I can make them work but I can’t make them pretty. I built my “Omega” petal a while ago, but there is a breadboard on my desk now with some half baked idea that just might make it into a box. Hopefully something will inspire you again.
Ralf,
I would say the first version might work. I have the equivalent of Barry’s Tone TwEQ circuit installed in my semi-hollow guitar as a pre-amp for the piezo, although I’m using 2 jacks and a modified Paramix board to mix the signals on the floor. Note, my piezo pickup just doesn’t play well with some effects, so try it before you modify the guitar. Mojo is hard to predict.
Awesome project, good luck,
Elio,
Raising the values of the input and output caps will pass more bass frequencies, but c7 and c9 may also need to be adjusted too. You may need to experiment with values to find your sweet spot, so if you decide to try to adapt the pedal I suggest using sockets to spare the board from repeated de-soldering. No worries about letting the smoke out.
-Best
In regards to pin identification, short answers is yes, I think you have the pins numbered correctly in the picture. However flipping the board over requires too much extra thought for me, I use the legs of the IC for checking voltages. From the top of the board, number 1 is the pin to the left of the little indent on then count down then over and up the other side.
As far as the wiring for the jacks, there is a “T” printed on the board to identify the pad that is connected to the Tip on the jack.
Now as far as the signal. You should check for output from both the send and the out jack. remembering the gain and mix pots should only affect the signal at the out jack.
Best
If your definition of DOA is that the LED doesn’t light up. The S4/S5/S6 pads are connections that should go to the foot switch to activate the LED. Without a switch or jumper there the LED will not illuminate. If you want the LED to be on whenever the board is connected to power, a jumper between S4 and S5 should do the trick.
Hope that helps
Be sure you made both ground connections and check your trimmer adjustment? Not really a thought just guesses.
Okay it’s a little early yet but I didn’t see any notes in the new build doc regarding the trimmer and adjustment. For that you should start around mid-sweep on the trimmer and make very small adjustments to find that spot.
Another basic question is, are you using a known good power supply?
The troubleshooting could be getting more technical from here. Do you have a Digital Volt Ohm meter?
It is nice to have an audio probe to be able to trace the signal path. I think it’s one of the best tools to isolate issues. By being able to verify a good audio signal at the input to the board you have a quick way to know which direction to go with testing (usually). It can also help locate problems on the board by following the audio path on the circuit.
For safety and simplicity, I use a 9v battery powered amp for bench testing. If I need an audio probe, I can clip it to the output jack on the build and test away using the amp to listen.
You can do some damage with a probe so be aware of what you touch with it.
If you build the tap tempo board with a voltage regulator, so you don’t have to tap VB from the delay board, ( see build notes ) I think it can work with just a patch cable.
You could de-solder the leg of R9 that connects to R22 and lift it from the delay board. ( sorry I don’t have a board to verify which leg that is ) Then connect a wire from that leg of R9 to the tip lug of your new switching jack. This will be your send to the tap tempo.
Then connect a wire from the ring lug of your switching jack to the pad on the delay board where you lifted R9. You will then have a switch that will separate R22 and the Time pot on the delay board from the circuit when you plug in your patch cable and connect them when the patch cable is out.
On the tap tempo side, just connect the tip lug of your input jack to the board.
If you use an external power supply that is daisy chained to both boards, I don’t think there will be any ground issues. I am unsure what would happen without a common ground.
I hope I explained that well enough.
I’m not a guru here, but I think the type of capacitor you used for C1 is a tantalum cap and it is polarized. If it is mounted reversed in an audio path, it will block your signal. If you don’t have a non-polarized cap handy to replace it, just flip that one around and it should work.
Keep in mind you can let the smoke out if you reverse the voltage on a Tantalum cap, that is one of the reasons I avoid them. It wouldn’t hurt to check it with a meter before reusing it.
Hard to see a lot of details. Looks like you used a a tantalum cap for C1 on the buff n blend board. If you did, be sure the polarity is correct. Positive should go toward input or R1.
It would seem that you would have to do the same thing twice to get the same result between two builds. Try something different. Consider using some sockets and populating C3. Start with a 22p and work up. If the extra cap doesn’t fix anything just take it out, no harm no foul.
Hi, I’m not one of the gurus here but I’ll try to help. Judging by the pictures you are bench testing your build.
If you are bench testing, be sure you have all the ground connections complete between the board, jacks and power supply, as per the build doc. A second note about bench testing is that enclosures shield the board from noise as well.
I spent some time bench testing mods for the Muff’n circuit recently. Through my experimentation I discovered a lot of noises that I wish I had recorded to have as examples for questions like these.
For troubleshooting, I think that the fact that your pedal is noisy when it’s off is a good place to start. If the board is properly bypassed, it should not affect the signal. Verify your cables are good and start testing with no input cable connected to eliminate those variables.
If you have a noise when powered off in bypass mode, check for a polarity or connectivity issue between your jacks. The signal goes from input jack to 3PDT board to output jack. That should be the easiest to trace and verify, this is usually a ground issue. Try a jumper wire between the input jack ground (sleeve) and the output jack ground.
If that is not the issue, but you have a noise when powered on in bypass mode, then you have some cross mojification, That would be some stray voltage or signal. A possibility would be Battery + connected to your signal input before or after the effect board or I/O wiring routed too close to a high gain board.
Billy mentioned external causes. One thing I discovered is that bench testing with an “open” or “no” enclosure can get very noisy if you have a shop full of old fluorescent light fixtures. I have to turn off the overhead lights or put the cover on the enclosure if I want to sound test in the shop.
Great suggestion by Cybercow, some transistors have flimsy legs that will not fit tightly in a socket.
I’ve been using hot glue since I saw it used in 6 Degrees FX pedals. It is non-conductive. Drip a small amount to glue the body of the transistor to the socket and it will stop it from moving. Obviously, I would only use it after the pedal is finished and tested, and I use “low temp” glue. I like the small “kiddie” guns that use the smaller glue sticks because they will get into tight places. I also use it for strain relief. A small drop on my board I/O wires helps keep them from breaking off at the board from too much movement during bench testing and it is a lot quicker to use as an insulator for wire to component connections rather than shrink tubing. One more advantage , you can peel it off to service or upgrade components. I use a quick spray with a dust-off product to freeze it to help with removal. Downside, it might not look pretty.
