Thursday, 14 September 2017

Null A - NLC Build notes.

Here are the build notes for the Nonlinearcircuit Null A module.
This is in Eurorack format.
It's a reasonably big build so probably not good for a newbie.
Though it has all the major modules one would want so if you feel game go for it.

 2 VCOs, 2 LFOs, 3 VCAs, 2 filters,  1 sequencer, 1 clock divider, 1 mixer, 1 S&H, 1delay, 1 headphone amp and a chaos generator.

Andrew's build notes are here:
His blog notes are here:

There are lots and lots of SMDs and 2 PCBs.

I've seen the golden goat.
 These lyrics are from the band "The residents". From the album "Our Finest flowers"

I've seen the golden goat
He would like to lick my throat
I know he's mean and poor
And he waits at my door

He's too weak to do me harm
But he has a big long arm
It fills my dreamy head
Then I shake and wet my bed

Well, there's something I must tell you
I need something I will swear

The only perfect love
Is the one that isn't there
Yeah, the only perfect love
Is the one that isn't there

More NLC wisdom.

Traditionally, in Aristotle's logical calculus view, there are only two possible values
(i.e., "true" and "false" or 0 & 1) for any proposition. 
This is also known as Boolean Logic and is the basis of modern computers.
But in multi-valued logic, there are more than two truth values.
For example, Ɓukasiewicz and Kleene accept the values "true", "false", and "unknown".
Fuzzy Logic is another example of a non-Aristotleian view of logic.
Here the truth values can be any real number between 0 and 1. It is employed to handle the concept of partial truth, where the truth value may range between completely true and completely false.

Not really sure what this one means.
DPT = Dipropyltryptamine ?
N,N-Dipropyltryptamine (DPT, also known as "The Light") is a psychedelic drug belonging to the tryptamine family, first reported in 1973.
Back to the build:
First components. The 074 op-amps


Using 4 x LM13700MX/NOPB
Mouser NO:  926-LM13700MX/NOPB

The module uses one PT2399. Its a guitar aUDIO processor/delay chip.
Mouser doesn't stock these. So found some on ebay.
Look for SOP 16 size.

There are three CMOS chips.
4024,4029, 4052.
Mouser numbers:

I'm using sizes SOIC-14/16, SOP-16
SOIC = Small Outline IC
SOP = Small Outline Package 

"A Small Outline Integrated Circuit (SOIC) is a surface-mounted integrated circuit (IC) package which occupies an area about 30 to 50 % less than an equivalent dual in-line package (DIP), with a typical thickness that is 70 % less. They are generally available in the same pin-outs as their counterpart DIP ICs. The convention for naming the package is SOIC or SO followed by the number of pins. For example, a 14-pin 4011 would be housed in an SOIC-14 or SO-14 package."

RL = resistor LED.
R176, R199, R217,261. These set the brightness of your LED. I'm using bipolar LEDs so picking 5k1 .... see how this goes..


Q11,Q12 & Q29
I used a MMBFJ108 replacement.
Mouser no. 771-PMBFJ108-T/R

1K Tempcos.
Right side of main PCB  
 Centre of main PCB

 Left of main PCB

 Installing headers.

 Lots and lots of jacks n' pots

A NSL vactrol. cheap as chips. K = cathode = white dot on the vactrol.

Couldn't find a SMD 10M resistor. So a through hole had to do.

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  1. Yes Possibly.... thanks I'll add it to the notes.
    Cheers Jono

  2. Should the pots be audio or linear taper?

    1. I used all B100K pots. The 1M are audio