Damaged 101? (resolved)

I just received a used 101/102 and I see something weird with tracks 2 and 4.

The range of CV I’m getting from all 4 CV outputs (A and B for each track ) is between 0-0.114V. I guess the unit is damaged but I’m really hoping I’m doing something wrong.

I updated to latest firmware and cleaned everything

Track 1 and 3 work fine.

Thanks for helping!

Have you checked to see if those tracks have a different scale loaded?

Scale you mean index table? Yes I have. I also tried to clean upgrade and downgrade…

You could try copy-pasting one of the working track’s tables, or a reference table, into one of the suspect ones, to see if that changes anything.

From the manual:

To copy a reference table:

  1. Set the TABLE switch to the REF position.
  2. If it is not already focused, press the INDEX button.
  3. Select the specific table with the RIGHT knob.
  4. Press the COPY button and the INDEX LED will flash.
  5. Now select table A or B with the TABLE switch.
  6. Press the INSERT button to overwrite the destination table for the current track. 7. Repeat step 5 and 6 for as many tables as you desire.
  7. Press the COPY button again to leave the copy mode.

May I have you follow this procedure and provide the resulting measurements?

  1. Load a blank snapshot (i.e. the ‘–’ snapshot).
  2. Put the MODE switch in the FOLLOW position.
  3. Navigate to track 2.
  4. Insert a single step (by default it should show the values cv-a=12, cv-b=10, dur=0, gate=0).
  5. Measure and report the voltage at Track 2 CV-A and Track 2 CV-B. (Should be 1.000V for both.)
  6. Change CV-A to 96 and CV-B to 80.
  7. Measure and report the voltage at Track 2 CV-A and Track 2 CV-B. (Should be 8.000V for both.)
  8. Please repeat (4) to (7) for Track 4.

Your report should include 4 voltage measurements for each suspect track for a total of 8 measurements.

Thanks for helping, something is obviously very wrong:

Track 2 CVA at 12 - jumps a lot, between 0.015-0.205, same for CVB at 10
Track 2 CVA at 96 a jumps a lot between 0.253 - 1.288, same for CVB at 80

Track 4 CVA at 12 - jumps between 0.024 to 0.036 Same for CVB at 10
Track 4 CVA at 96 - jumps 0.137 - 0.201, same for CVB at 80

Thank you for the measurements! Just to confirm, if you do the same thing on Track 1 do you get the expected 1V and 8V?

Also, may I have some high resolution photos of the DAC? Especially concentrate on the area between the DAC and the jacks for Track 2 and 4.

Track 1 looks fine

Update: I cleaned the board with special material for PCB cleaning. Now the numbers look better. They are far from perfect, but at least close (kind of) to 1v and 7-8v.

I reinstalled the firmware (was thinking maybe it’s a calibration issue and is done after installing). Didn’t help.

Another issue is that the numbers still “jump” on all 4 CVs.


Do you have access to a hot air reflow station? What you describe sounds a lot like cracked solder joints on the DAC. Often just reflowing the solder will fix cracked solder joints.

I do. So just “reflowing” the dac?

Also, is there a calibration process at all?

Yes. Especially the left side which has the pins for tracks 2 and 4. Also, make sure you cover the PCB holes that are drilled behind the jacks with Kapton tape or similar. You don’t want to melt the plastic housing of the jacks.

No calibration is necessary.


Thanks sooooo much :))


I’ve been lurking on this and just wanna say that I think this is a shining example of the care that @odevices shows for the community here :star2: :star2: :star2: :star2: :star2:

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Good work @Joey!



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I’m seeing another issue, might be me doing something wrong though:

Im trying to play with the modifiers, x works fine with gates high and low (I’m just adding and subtracting 12 to CVA). Problem is that I can’t get the exact same thing to work on y and z. Nothing happens

Also, when I try to monitor the CV in for all 3 in slope, x shows the correct value while y and z show 0.

I’m brand new to both modules, maybe I’m doing something wrong

Ideas ?

Here is a test procedure to make sure mod channels X, Y, and Z are ok.

  1. Turn on your modular while holding down the INVERT and ROTATE buttons.
  2. tESt should flash briefly on the ER-102 and then all the ER-102 LEDs will start flashing.
  3. Patch a known good cable from Track 1 CV-A to mod channel X CV.
  4. Note the value shown in the ER-101 VOLTAGE display. It should be 1.000V +/- 0.003V.
  5. Repeat (3) and (4) for mod channel Y and Z (and, if you like, all of the analog inputs on the ER-102).

Please report your findings.

XCV is fine, Y and Z show “none”…

A1 and A2 are also fine

So, if I gently touch the back of the 102 PCB it works for a few seconds and stops working. If I touch again, works for a few seconds again