Okay, so these are standard size 16mm Alpha pots. Not sure where are you located, but Banzai has them too: http://www.banzaimusic.com/Alpha-16-DET-10k-lin.html It's a full shaft version with solder lugs, not PC mount as the original, but it's not a big deal. A piece of solid 1mm diameter copper wire...

Looks like it might be one of the 11 detent ALPHA pots, like this: http://www.banzaimusic.com/Alpha-9-PC-DET-10k-lin.html The exact value will be less relevant. I'm guessing it's used as a switch supplying DC levels to an MCU, a common way to use a pot as a switch. 10k linear should be okay. Post so...

Can't see what that chip is, but i used a 4532 priority encoder for that purpose (1P8T switch into binary output) in the past.

http://product-images.highwire.com/4789 ... aniod4.jpg
you can clearly see it's FV-1
My guess would be:
Mode switch: S0..2
Rate: FV1 pot input
Step: FV1 pot input
Toggle switch: FV1 pot input
the rest of controls are analog.

Did you do these tests using a AC adapter or a battery power? Cause, if you are using the 9VAC adapter, you have just removed the main filter capacitor basically supplying the pedal with AC voltage while measuring the DC voltage. Of course, it doesn't mean you should switch the meter to AC and take ...

Try swapping the DIN 4-5 wires and see what happens.
The best way would be to scope the signal, you can also try a simple midi led tested to see if there is any transmission:
http://www.epanorama.net/circuits/miditest.html

Not really. I guess this is not a simple task if you are not into digital stuff, programming, etc. Pedals are using custom midi messages, specific only to their type, one Jamman looper is sending out commands that only the same or similar type of device can receive and decode. As far i can see there...

I have just built that circuit to check the output with a logic analyzer. It turns out it's even simpler. Jamman Express XT sends plain MIDI sysex messages to control the slave device. All you need to do to see the data is to make an adapter cable: Minijack TIP -> DIN5 (4) Minijack RING -> DIN5 (5) ...

I have done that, but only briefly, didn't have enough time to analyze the data. The sync signal on the Jamman Xt, which i got is actually a midi type signal (UART, opto isolated current loop, 31250 baud). If it's a normal midi protocol or a some kind of proprietary one, i don't know (yet!). However...

Any chances for taking out the second board and making a few more shots? I'd be interested to see digital part of the circuit. Thanks!
Looks like the tactile switch is not smt, but regular through-hole:

pz: it seems to be preety much what I am looking for. Maybe a scheme will be helpfull. I will not switch it off, it should stay forever on, so opto won't be needed. Maybe a question for your desing: does your circuit has ripple issues when signal fades away...? As I said, a scheme should be very he...

What i have done in my amp and few other builds when it comes to noise gating: - use a high input impedance FET buffer and take the signal directly from the input of the amp - use it to extract the envelope driving the noise gate - the main switching element (i used H11Fx opto FET) that gates the no...

Most likely only for the Ethernet (impedance matched pairs going from the RJ jack), midi, usb and other control/comm stuff.
The PCB on the left has "Profiler DSP something" text on it. DSP is presumably on the other side.

Great build johnk!
I have updated the PCB design a few days ago and got the pcbs fabbed: There is a small change in drill layout (ON/OFF led). All the new design files are here:
https://github.com/hexeguitar/Tadek-Compressor

R14 = 220k ??? Usually it's in range 220R-1k. Probably a typo.
No MIDI thru?

Thanks guys! :arrow: smackoj a proper piezo preamp could be much simpler than the circuit i presented. Usually, what you expect from a piezo pre is to have relatively high input Z (10M or more), a gain control, maybe some sort of high and low pass filters (removing unwanted low end, presence control...

Here's a small gadget i designed to help me with developing stereo, mostly DSP based effects: Dev_LOOP[/b] https://i236.photobucket.com/albums/ff176/314_tr/Dev_LOOP/Dev_LOOP1_zps748efce7.jpg a versatile stereo Hi input Z preamp / effect loop Design goals: Mono/stereo operation with versatile IO rout...

The 100k resistor at the end FF stage should go to the base of the 1st BC182 instead of the emitter (=GND).

There is one gyrator missing on the schematic. Hint: take a closer look at the inverting input of the IC1A.

One way around it would be to determine the max allowed signal amplitude, that still does not turn on the clipping diodes completely and clip the signal at the first stage using diodes etc. A small resistor in series with the output stage ensuring it sees a resistive load when the Level pot is at ma...