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Here is my Sunking 2015 with patriotic colors and Abbie Hoffman tribute.  It cuts out when gain is around 3 O'clock with a weird whine, then comes back, so I'm going to start swapping/checking the charge pump.   Clipping diodes are very subtle to me (on/off/on with red led's and 1N34A), but I'm tone deaf, going to let some friends play it. 

Awesome, love the look of it.

See if this helps.

Range "A" means pole A of the range switch.  Range B means pole B of the Range switch.  You have two logic switches you are controlling with one toggle.  So, two switches in one. 



when the toggle is one way, pin 2 it connected to pin 1, for both A and B
when the toggle is the other way, pin 2 is connected to pin 3, for both A and B poles

Also, the Range switch is a 2 pole switch as well, meaning two different spots are switched when you toggle.  So A and B are switching when you toggle the switch.  So, when pin 2 is connected to pin 1 on both A and B, that is one position of the switch.  And when pin 2 is connected to pin 3 on both A and B, that is the other position.  So two poles, two position, or Dual Pole Dual Throw, or DPDT.  3 Poles with 2 positions would be 3PDT (like the stomp switch)....

I'm having a similar issue on a PCB i made for myself, so i'm interested in any help as well.   The Hi/Lo switch is a double pole switch, so switched one way, both stages (vacatrols) have one value of capacitor, switched the other, they both have the other value.  So don't thing there is any issues there

The up/down is for the envelope portion that you have shown.  Either sweeps up with the enveope or down.  All I can offer is try changing the input gain over it's range and see if you can get it to engage, also try varying the sweep trimmer.  Take some voltage measurements on Pin 7 of IC2 when in up and down positions.

Hopefully someone else can chime in.

well i guess on vac vs the other could be engaged based on hp/bp/lp, actually.  i'm mucking with this circuit as well, but have not traced the hp/bp/lp thorugh the filters to understand it yet.  glads its improving otherwise.

vactrols are always engaged.  they effect the filter, so the envelope modulation is running through them.  did you get a DPDT on on on switch for the hp/bp/lp filter?  Three position, right?  If it is on off on, then that could be an issue.  just thinking out loud.  i think there are two types of on on on.  is it the center position that buzzes?  that info may help trace to your problem. 

OK, cool.  I didn't read all the previous.  Not sure what to look for next, but reflow all the joints, check for reversed component positions, etc.....   

IC4 Pin 1 is the pad that is square.  If you socketed it, just remove the IC and bend that pin upwards so it will not go in the socket, then put the IC back in.  IC numbering goes from the end of hte IC that has the half moon indention, when that is the top, pin 1 is on the left, pin 2 below that, then wehen you get to the bottom, you keep going around counterclockwise so the bottom right most pin is pin 5, 6, and 7 going up the right side.  If there is no half mood indention, then it is marked with a circle.

No need to break any traces on the board.  Did you do that?  If so, tell us where you did that, if you had the numbering off, this could be an issue.

If using LT1054, you need to lift pin 1.  It can't be connected to pin 8 like the others.  Did you lift pin 1?

also, if you are testing outside a box, make sure your input and output jacks are grounded.  if you follow the build doc, your output may need to be grounded

are IC4 pins 4 and 5 positive or negative?

I'm not good at this, but I've made a few of these (still troubleshooting one).  Check to see if you have +9v on pin 7 and -9v on pin 4 of IC4 and IC5.  At the same time check for +9 on Q6 drain and Q4 emitter.  and -9v on Q4 collector.

the sample hold side is Q4, IC4, Q5, IC5...

Do you have multi turn trimmers?  or single turn?  It can be strange to find the working spot, but following madbean instructions should get you there if it's working.

very nice, like the stripes. 

Thanks!  John, glad you remembered it.  Forgot I had a video.  first part is what I wanted to mimic, the filter skirting on the edge of off/on for a bit in envelope mode.  Second part is me messing with the random LFO.  This was the first build.