NLC Dispersion Delay - build notes -part 1

These are my build notes for the nonlinear circuits Dispersion Delay

Its a eurorack format module.

Some pics of the virgin PCBs and panel.

This module is based on ideas suggested by Lucas Abela. It is three vactrol based bandpass filters in parallel, each filter is fed into a voltage controlled delay stage. The outputs are available individually or there is an OUT ALL where all 3 signals are mixed.

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Before beginning, three 100k and three 47k resistors should be replaced with 220k.

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 + Integrated circuits - packaging 

The delay chip

tHE voltage regulator

This module uses 9 vactrols.
You can make your own if you like.
Try to choose ones with low on & off resistances.

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Andrew's notes; "If the datasheet for your chosen vactrol or LDR shows the minimum resistance as more than 1kΩ, then you can replace the 470R* on the PCB with a link or much lower valued resistor, say 10Ω.
.If none of this makes any sense, just install 470R.(R = Ω"

I'm installing 470R.

I'm also installing 470R for the LEDs (RL)

I decided to try rolling my own vactrols ... just for fun.

There are 9 of them to do.

testing shrinkwrap first.

Of course if you have a 3D printer then make your own light tight boxes.

Im inserting the LED side in first.

remember that the short lead is the cathode. = K

 The yellow shrink wrap is to prevent shorts.

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to be continued................. 

Part 2 is here

NLC Dispersion Delay - part two.

Links
+ NLC Wiki
+ NLC Build guide and BOM
+ NLC Blog (old)
+ NLC blog (new)
+ Blog re the delay
+ CMOS  info 
+ NLC DIY info
+ Nonlinearcircuits Builders Guild on FB
++ Integrated circuits - packaging


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