SOLVED Spatialist Reverb

[Morgoth]

Hi,
I've build the spatialist reverb pedal, but it doesn't work. All 8 programs are the same (nothing happens when i turn the pot), none of the upper controls (parameter 1, 2 and 3) seem to work, although when I turn the parameter 2 pot while turnig I hear some funny pitch shifting noises. But it doesn't matter if its on 0 or on 10, i can't hear any difference.
Does anyone know what might be wrong?
Thx!

 

[phi1]

Post pics!

Does the mix knob have any effect? With the mix knob maxes, is there no signal or just dry?Are you comfortable using a multi-meter and audio probe?

 

[Morgoth]

Here are the pics
Yes, the the mix knob works and so does the volume, i also found that paramter 1 (dwell) works.
I know how to make some basic measurments (for example check the voltage) with the multimeter. But i don't have an audio probe.

 

[phi1]

Audio probe is easy to build, basically just a cap and a jack and some wires.

But if the reverb is working you might not need one.

Do you have anything protecting to the bodies of the mix and vol pots from touching the board?

 

[Morgoth]

Yes a rubber pad is glued to the bottom of the volume and mix pots. Also i didn't see any pads connecting to each other (two pads soldered for example)

 

[zgrav]

please post a detailed photo of the other side of the PCB

 

[Morgoth]

Here you go.

 

[zgrav]

do a couple of google searches and build an audio probe. that will let you see if the audio signal is reaching pins 1 and 2 of your FV-1, and if the signal does go in there, you can see if it is coming out on pin 28. that will let you narrow your troubleshooting to either the signals going in or out of the chip, or see if the problem is in the FV-1.

where did you get your FV-1?

 

[Morgoth]

Ok, I will build an audio probe. I need to order some componets first. I will let you know how it turned out, when i get the components and build the probe.

 

[phi1]

I’m still not clear on what problems you’re experiencing. If you’re getting reverb sound and the mix knob works, then the audio probe might not be necessary right now.

Is the rotary switch changing the program? If not, check the voltages on fv-1 pins 16, 17, and 18 at each position on the rotary knob and post those results.

Are the parameters controls not working? (you slide dwell is but not the other two, keep in mind they are subtle on some of the patches). If you’re sure those controls aren’t working, check voltage on pins 20, 21, and 22 as you move the knobs. Voltage should be 0v at knob minimum, 3.3v at knob maximum. (Pins 20=control 1, 21=control 2, 22= control 3)

 

[zgrav]

you can do other checking with your DMM to see if your parts connect where they should in the schematic. the audio probe is a quick tool to use when you already have it, or can put one together out of spare parts you have in your inventory. so order what you need but don't let that stop you from trying other things while waiting for those parts. if you fix the problem before the parts arrive, then you build the probe to have on hand the next time you are troubleshooting a project.

 

[Morgoth]

@phi1, yes i get the reverb sound if the mix pot is not at 0 (100% dry), so the mix pot works, and so does volume. I also found that the dwell pot (control 1) works (it changes the length of the reverb), if I turn control 2 i hear some funny (kinda pitch-shifting) sounds (while turning), but i don't notice any difference if the pot is turned fully cw or ccw, if i turn control 3 nothing happens.
Also, if i turn the rotary switch nothing happens (sound stays the same, it doesn't cut out between the changes - it's like nothing has happened)

This are my measurements:
The first table is for the rotary switch, the scond one is for the controls 1 to 3


PS i would like to point out that all pins of the FV-1 are soldered to the board, i've double checked

@zgrav, yup will build the probe even if we manage to solve this, after watching some videos on youtube it looks like a cool and useful tool.
Also i forgot to reply to your question where did i buy the fv-1. I bought a kit from Musikding:

Spatialist Reverb kit, 66,00

Eight Reverb Modes

www.musikding.de

 

[phi1]

The voltages on s0, s1, and s2 should change as you move the rotary positions, so you know there’s a problem around there. Study the schematic in that area. Check for 3.3v on the center pin of the switch. Check for 3.3v on the perimeter pins for each position you change it to. Check that each of the s0, s1, and s2 pins has 100k resistance to ground. Check that the diodes conduct (should have a forward voltage around 0.5v to 0.7v).


The voltages for the pots look right, so it’s weird that you aren’t hearing a difference. On the other hand, on program 0 (Room Reverb), pot1 is pre-delay time, so a little pitch shifting as you turn that pot does make sense. Maybe the pots are working fine, but it’s hard to tell the difference? Some other patches would make it more obvious if the pots are working.

 

[Morgoth]

I've measured the voltage on the center pin and it is 3.3v, on the perimeter pins the voltage was always 0v on all positions. The resistances are around 100k on all 3 pins. The diodes are like this: D1- around 0.296, the rest (2-10) are from 0.706 to 0.716.
I did some additonal testing with my guitar and noticed that if i push the shaft of the rotary switch to the pcb, or maybe even if i push it to one side (i'm not really sure what of those two things works - the main thing is if i push the shaft of the switch somewhere) i get the right program sound - as soon i let it go, i get the "default" program again. Is it possible that i broke the rotary switch or that i got a defected one?
I've desoldered the switch and soldered again to the pcb, but nothing has changed.

 

[phi1]

Ah sounds like a defective switch, bummer. I doubt you would have damaged it by handling it, or if you did it wasn’t very high quality. See if pedalpcb will send you a new one.

 

[Morgoth]

Thank you both! i will just order a new switch and hope it will work.

 

[zgrav]

In the meantime, go ahead and reflow the connections between the rotary switch and the pcb and see if that helps, making sure to include the connection to the central pin that connects with all of the others when the switch is rotated.

 

[Morgoth]

I received a new switch and replaced the old one with it. Now it works like a charm. Thank you all for help!