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Doing it myself is on the table- the PDF withi. The zip showed what looked like a commercial circuit board along w the etching option.  I thought maybe it existed somewhere on the site and I was just missing it.

Mr Haberdasher doesn't appear to have that board but thanks for the suggestion

Hi All-

I'm just wondering if there's a resource where the Etcher's paradise  projects are in some sort of kicad/eagle/etc. format?  I haven't done any press n peal, etc., and if there were I'd probably rather order a handful of PCB's from Seeed or Oshpark.  Sorry in advance if this question isn't kosher.

Thanks for taking the time to reply.

I'll have to validate the vactrol again - maybe I have it wrong.  I'm traveling so it will be a couple days.

I measured the previous resistor outside of the circuit that measured as 0.  At this point I've reflowed most of the solder joints as well as replaced off board wiring to the pots (I didn't board mount them).  When I previously troubleshot this I had a bit of a heavy hand w/ the soldering iron so perhaps I've damaged the board.

Once I get back from my travel I'll try to follow the schematic (not particularly experienced but now's a good time to start).   Thanks again for your replies.

Oh, well that is clearer then and good news.

Something is amiss from the vactrol onward.  Check every spot from the vactrol to the delay time pot by following the schematic.  Check your value of R20 too, as if you have an incorrect higher value there it will reduce the modulation.  Use your continuity setting on your DMM to make sure you have continuity where you should.  It's likely something simple as there really is not much between the indicator LED and the delay pot.

You don't need to worry about jumpering the switch pins.  That was before you mentioned it was blinking in time with the speed pot.

Josh

Last night I replaced the Vactrol and R20 - I wasn't happy with the Vactrol soldering and the leg broke off when I tried to re attach.  When I removed R20 and tested w my DMM it showed no resistance so I replaced with a new 180k.  The modulation is still a bit weak but it has def improved.  I may further replace R20 w a lower value-added haven't decided.

Thanks for your help.

Sent from my Pixel 2 using Tapatalk

If you bridge the SW1 pads do you have the same effect?
Does the LED light?
If not double check the LED polarity.
if not that check R20 etc and the depth pot for any weak solder joints.

Your voltages look good assuming that the PT2399 was just read as pin 9 being pin 1...
IC2 is the oscillator for the modulation, hence the voltage swing.

Josh

Thanks for the reply.  I will bridge the pads tonight and report back.

The LED does light up at a rate that changes based on the speed pot.  If I turn the mod off (with either switch) the LED also turns off.

Sent from my Pixel 2 using Tapatalk

Accidentally posted this in the wrong area so apologies for the duplicate post.

Have the 1776 Multiplex Jr board.  Delay is working fine, and I hear a slight modulation when it's engaged.   I made one only one modification - I added a DPDT footswitch along w/ the SPDT so that you can turn the modulation on or off with the regular switch or foot switch.  I removed the modification and still experienced the issue.

This is the documentation from 1776: http://1776effects.com/wp-cont...s/2015/03/Multiplex-Jr-BOM.pdf

Here are the voltage readings I've taken (IC# taken from the above doc)

IC1
1 4.24
2. 4.24
3. 4.25
4. 30-40 mV (fluctuating)
5. 4.27
6. 4.27
7. 4.25
8. 8.48

IC2 - This IC had fluctuating values.  The notation I'm using below indicates fluctuating between value although the numbers aren't exact. The fluctuation generally isn't slow, it's like it's bumping around ~1 or 2 v at a time
1. 5.24/3.5 V
2. 5 / 4
3. 4 / 3
4. 48 mV
5. 5.3 /3.3
6. 5 / 4
7. 8.5 / 0
8. 8.5

IC3
1. 2.55
2. 2.55
3. 2.55
4. 2.55
5. 2.55
6. 2.55
7. 2.55
8. 2.55
9. 5.06
10. 2.55
11. 22.2 mV
12. 22.2 mV
13. 2.93
14. 2.54
15. .675 V
16. .711 V

Reg
5.06 V
22.2 mV
8.5 V

Sent from my Pixel 2 using Tapatalk

Accidentally posted this in the wrong area so apologies for the duplicate post.

Have the 1776 Multiplex Jr board.  Delay is working fine, and I hear a slight modulation when it's engaged.   I made one only one modification - I added a DPDT footswitch along w/ the SPDT so that you can turn the modulation on or off with the regular switch or foot switch.  I removed the modification and still experienced the issue.

This is the documentation from 1776: http://1776effects.com/wp-cont...s/2015/03/Multiplex-Jr-BOM.pdf

Here are the voltage readings I've taken (IC# taken from the above doc)

IC1
1 4.24
2. 4.24
3. 4.25
4. 30-40 mV (fluctuating)
5. 4.27
6. 4.27
7. 4.25
8. 8.48

IC2 - This IC had fluctuating values.  The notation I'm using below indicates fluctuating between value although the numbers aren't exact. The fluctuation generally isn't slow, it's like it's bumping around ~1 or 2 v at a time
1. 5.24/3.5 V
2. 5 / 4
3. 4 / 3
4. 48 mV
5. 5.3 /3.3
6. 5 / 4
7. 8.5 / 0
8. 8.5

IC3
1. 2.55
2. 2.55
3. 2.55
4. 2.55
5. 2.55
6. 2.55
7. 2.55
8. 2.55
9. 5.06
10. 2.55
11. 22.2 mV
12. 22.2 mV
13. 2.93
14. 2.54
15. .675 V
16. .711 V

Reg
5.06 V
22.2 mV
8.5 V

Sent from my Pixel 2 using Tapatalk

Have the 1776 Multiplex Jr board.  Delay is working fine, and I hear a slight modulation when it's engaged.   I made one only one modification - I added a DPDT footswitch along w/ the SPDT so that you can turn the modulation on or off with the regular switch or foot switch.  I removed the modification and still experienced the issue.

This is the documentation from 1776: http://1776effects.com/wp-content/uploads/2015/03/Multiplex-Jr-BOM.pdf

Here are the voltage readings I've taken (IC# taken from the above doc)

IC1
1 4.24
2. 4.24
3. 4.25
4. 30-40 mV (fluctuating)
5. 4.27
6. 4.27
7. 4.25
8. 8.48

IC2 - This IC had fluctuating values.  The notation I'm using below indicates fluctuating between value although the numbers aren't exact. The fluctuation generally isn't slow, it's like it's bumping around ~1 or 2 v at a time
1. 5.24/3.5 V
2. 5 / 4
3. 4 / 3
4. 48 mV
5. 5.3 /3.3
6. 5 / 4
7. 8.5 / 0
8. 8.5

IC3
1. 2.55
2. 2.55
3. 2.55
4. 2.55
5. 2.55
6. 2.55
7. 2.55
8. 2.55
9. 5.06
10. 2.55
11. 22.2 mV
12. 22.2 mV
13. 2.93
14. 2.54
15. .675 V
16. .711 V

Reg
5.06 V
22.2 mV
8.5 V

Super old post that I'm replying to, but wondering how /where you added the Mix knob?

Sorry for the delay - that was exactly the issue.  The effect isn't as pronounced as in demo videos on Youtube, but I'm gonna chalk that up to production values.

I'm working off of this layout:

http://tagboardeffects.blogspot.com/2016/11/earthquaker-devices-tentacle.html

Schematic:
http://imgur.com/7trLVjz

Album of board:
http://imgur.com/a/6NGxf

Troubleshooting:
Measured Transistors and Resistors, used sound probe. 

Outcome of troubleshooting:

• R3 is supposed to be 160k, but when it's on the board it's only measuring @ 125 (replaced with a new resistor that I measured at 160k off,  reading 125k once it was on the board).
  
• 4 resistors had no audio on one leg - see the circled spots on the diagram http://imgur.com/IdOADyb
  
• Q3 had no audio on the C leg
• Ran razor between the traces to try to ensure no bridges were there
  
• Verified transistor pinouts to make sure I had them in correctly (I did)
  
• All pins on transistors had audio
  
• Transistor Measurements

Transistor	C	B	E
Q1	5.13	2.04	1.47
Q2	3.65	5.18	5.81
Q3	9.4	4.3	3.82

Not sure what to do next.  The resistors that don't have audio on one leg all measure out ok, so I'm not sure why they wouldn't at least have some passing through.  Admittedly I don't really know much at all about electronics so I hope what I'm telling you is helpful.

Thanks in advance![/list]

Awesome thank you for the added information!

Probably a stupid question that I can't find the answer to.  Does anyone have a description of what the 5 pots for the multiplex jr control?  E.g. is depth controlling the depth of the modulation or echo, etc.

Here's what I'm hearing, but I'd like to be positive before I give it to a friend.

Mix - Mix of dry and wet sinal
Time - Length of delay
Feedback - number of repetitions of the delay signal
Depth - Depth of Modulation
Speed - Speed of Modulation