Thursday, 30 November 2017

CellF Action - Build notes

Finally getting around to this.
Andrew put these out in 2015 (along with the CellF Voice).
Andrew's build notes are here:

A big-ish build I think.

Some closeups of the PCB to help with later troubleshooting.
Right of PCB

Centre PCB

Left PCB

The Action panel uses three NJM13700
They are current controlled transconductance amplifiers.
I'm using the same components I used on the cluster build

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."
 There are 5 fixes needed to the slew of the logic module.

 I added the 47K resistor to the underside of the PCB

gETTING there. Just waiting on some components from Mouser.
This is a big build.
ICs and most of the SMD passives are in.


Having trouble sourcing the TLP291-4 - quad opto-coupler package. ?? Mouser no
I'm trying these:

LED resistors.
I'm using 1.5K resistors for the RL components.
Andrew's build notes for the Cell F Voice panel said:
For regular LEDs use RL = 330Ω-470Ω
forultra/superbrights use RL = 4k7Ω-10kΩ

I may have to change this once I get the board up and running.
Easy enough to do with SMD .


Time for the pots and jacks
 Notice the height of the jacks. The switch is taller than usual and this is forcing me to raise the level of the jacks & pots.
 Soldering the pots was a tad tricky. 

You will need 4 of these JFETs

These are the 1K tempcos draped over transistors in QUO and VCO sections

fINAL pics.

+ NLC Build notes for Cell F Action panel
+ Build notes for Cell F voice

--------------------------------------------------------------------------------------------------- Click here to return to the NLC Build Index:  

Tuesday, 28 November 2017

Brain Custard - NLC Build notes

My notes for the Nonlinearcircuits Brain Custard Eurorack module.
This version of the module will be for audio rates, but you can also build this to produce CVs.

It's kind of like the Jerk Off module in that it uses chaotic oscillators.
The Brain Custard has "9 audio rate chaotic signals mixed to form 'neuron clusters'
The idea is that the low frequency patterns will emerge from the mayhem.
Really it will be vaguely controllable noise and lots of it.....with LEDs."

No rare or hard to source parts. Yah !!!
Just four TL074s & one TL072
Mostly SMD passives.
"c" = 100K
"1" = 1K

For the Audio version install all eighteen 10K resistors.
For the CV version six of the 10k resistors need to be replaced with 47k resistors
Some very good advice. :-)

I like to install the ICs first.

"Inputs can be anything; audio, gates, triggers or CV. Depending upon the pot settings, the input signals may do a lot or do little. The X, Y & Z outputs are mixes from the same stages of different oscillators, consider them minor Σ (sum) neurons. Custard is just everything jammed in together, so the main output neuron. Blend is the X, Y & Z outputs mixed together via the Blend pots, these pots have +/-1 gain, meaning when the pot is at 0 the signal is inverted and if the pot is at its mid-point the signal is off."

+ NLC Build notes
+ NLC Blog

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Nara Japan

Some pics of Nara.
A very short bus ride from Kyoto (1hr). Well worth a visit.

Below is Todaiji Temple. Constructed in 752.
Todaiji's main hall, the Daibutsuden (Big Buddha Hall) is the world's largest wooden building,
The present building is a reconstruction, built in 1692. The original hall was 1/3 larger than todays building.

Nara used to be Japan’s capital. It was founded in 710 AD. The capital was moved to Nagaoka in 784 in order to lower the temple's influence on government affairs..

Along the approach to Todaiji stands the Nandaimon Gate, a large wooden gate watched over by two fierce looking statues. Representing the Nio Guardian Kings, the statues are designated national treasures together with the gate itself.

Deer roam in Nara Park, site of Tōdai-ji temple.

Daibutsu, Tōdai-ji's 15m-high bronze Buddha, is displayed in a large wooded hall.

Kasuga Grand Shrine is a Shinto shrine in the city of Nara. Established in 768 AD


For more travel postcards click here: