Wednesday 13 March 2024

NLC - LDRama - build notes

 These are my build notes for the nonlinear circuits LDRama module.
tHIS eurorack 28HP light sensor module  was designed upon suggestions from Alex Brunori. 
The idea is to play a video (or skype or whatever is the newest thing) fullscreen on your phone and place the phone on the LDR array. The module will generate CVs in response to what is happening in your video.

I've got a Arduino controlled LED project in the works, and I'd like to see if I can do something interesting with the two.

links
+ BOM

I think this is a pretty neat idea.
It is designed to suit a typical 5x2 inch screen, larger screens work fine tho some info around the edges is lost. Ideally the module will sit flat, if on an angle patch-cords into the top row of jacks hold it up very nicely


You can also patch in an external signal, such as a CV from a sequencer, and process this thru the LDRs.


The BOM suggests using GL12528 LDRs x 48


get the opamps on first.
TL072 x 15


















resistors next.
lots of 1k and 100k




These 8 resistors marked 100k should all be 1k
The RL and 1k should be swapped
2k2 resistors for RL












I'm using a 10R resistor for reverse
voltage protection


The LDRs are larger than the usual
You need 48 x GL12528
on order from ebay

to be continued.....

-----------------------------------------------------------------------------------
You can find more NLC builds here.
--------------------------------------------------------------------------------------

Sunday 10 March 2024

NLC Stochaos - Build notes

These are my build notes for the nonlinear circuits "stochaos" module.
It's a 8hp eurorack.


STOCHAOS...... It's a random rhythm pattern generator or sequencer which produces gates and control voltages 














There are just two inputs ; IN & RST
Everything else is an output


Links


This is a decent sized build using 2 PCBs
Start with the ICs and transistors.

The module uses a lot of cmos
CD4070  x2....... XOR
CD4040 x2  .... clock divider 



CD4040 clock divider's outputs feed the four binary inputs of a CD4028 BCD to Decimal converting chip, creating pseudo-random sequences, depending on different CD4040 outputs feeding different CD4028 BCD inputs.


"The circuit can be easily modified by replacing the two 4070 XOR chips with two 4081 AND chips (or any other 4 channel two input logic chip – OR, NAND, XNOR, NOR). I might Build both versions ....the one-gate-at-a-time version tends to get a much faster clock signal" (Andrew F). 




CD 40175... Quad D-type Flip-Flop















CD 4028....... BCD-to-decimal Decoder






























Resistors

Pink noise level :
*** 1M-10M? x 1 ........................select for pink noise level .
................ im using a 10M

RL (LED resistor)  x 9 ..............select resistor to suit LED
brightness (prob 4k7 to 10k) ..... im using 4.7K



....
power rectifier BAT54GWX


Diodes
LL4148

5mm LED for chaos circuit on top PCB, any
crappy LED is fine but high V-on is
good so a blue one if you have it.

headers to unite the two PCBs





















switch

SPDT - 
on-off-on














Jacks

3mm LEDs x 8 ....Up to you, diffused lens are easier
on the eyes. Square hole = anode 


I always do these last.

You're there


First tests.
The LEDs light up. That's promising.



the input needs a SAW or SQUARE wave 
Sine & Tri waves don't trigger the module very well.

-----------------------------------------------------------------------------------
You can find more NLC builds here.
--------------------------------------------------------------------------------------

Saturday 2 March 2024

CMOSC - Drone Oscillator - Build notes - Nonlinear Circuits

These are my build notes for the Nonlinear Circuits CMOSC module
Its a eurorack format module.

CMOSC is an updated version of the 
4U CMOSC (CMOS drone Oscillator). 

Each module has 6 oscillators; the frequency of each
oscillator can be set with the pots. Feeding a signal to 
input will decide which oscillator signal will appear at the output. If the signal is low, oscillator A is heard, if the 
signal is high oscillator B is heard. 
This module gets very interesting when the outputs of each oscillator pair are fed into other pairs, which are themselves controlled by others and so on…..complex, evolving drones. Put
patchcords into every jack so every pair is controlled by another pair, listen to one of the outputs, twiddle the knobs until you feel satisfied.
The sync input actually disables the oscillators, the unmarked output is a sync output…or if you like; it goes high when the oscillators are disabled. It is most interesting to put an audio signal into the sync input, preferably from the other CMOSC module




The Eurorack CMOSC also  consists of 6 oscillators. 

each can be switched between two frequencies set by a single pot. When the pot is in the mid-point the two frequencies are about the same. Turn the pot to min or max to switch between higher and lower frequencies, or lower and higher. 














It's a gated oscillator.
Meaning  Each oscillator controls the switching of its subsequent neighbour
 (1-2, 2-3, 3-4, 4-5, 5-6, 6-1) via the switching pins of the input jacks. 
Patching in a signal will break this cacophony and allow you to have some control over proceedings.

Links
+ BOM







No hard to find parts



A single atom deprived of vibration could wreck the universe.
William Walker Atkinson

---------------------------------------------------

"there's only so much you can do with a op amp "... Paul S

CD40106 1 soic Mouser: 595-CD40106BM96 or 771-HEF40106BTD-T



CD4053 2 soic Mouser Part No: 595-CD4053BM96 or 771-HEF4053BTD-T



TL074 or TL084 2 Soic Tayda: A-1140 or A-1137


LL4148 x 7 sod-80 Tayda: A-1213
BC847 x6 SOT23-3 Tayda: A-1339 
Resistors: 1k, 10k, 100k, 220K



The two 5V1 Zeners (SOD80) are optional..... I'm leaving them off for now.
The function of these 2 zeners is to keep the output of the summed stage to 
exact Eurorack …ahem…‘standards’.
The individual outputs generally swing between +/-5V (so 10Vp-p) anyway, which is pretty much
within the "standard range so I don't think I'll need them.
(The pads for the 5V1 zeners are there if I change my mind).
The summed out is very noisy and raw.

I'm using a 10R instead of the Schottky (for the rectifier).
Just don't plug the power supply in backwards. 

caps
C1-C6 set the frequency range for each oscillator. 470nF gets down
to approx. 15Hz, so is probably the highest value you want to use
(assuming you want to keep things in the audio range). 
Andrew says its OK to mix values or keep them all the same.
I've decided to use all 470nF. Ill see how this sounds, then might experiment later.

*** I started to experiment with these caps. Changed C1 , C2, C3, C4 to 220nf.
      the drone was more audible*****


The other caps are 10uf and 100nF


Soldering the headers that join the two PCBs.

Pots & jacks.


You're done 




-----------------------------------------------------------------------------------
You can find more NLC builds here.
--------------------------------------------------------------------------------------

AVR Programming -- AVRDude etc

 Some notes on how to upload a hex file using AVRdude.
AVRdude is a program to upload or download to on-chip memories of Microchips AVR suit of Microcontrollers.
 
 

Links
 
You can also use something like this:
 
or this:
https://core-electronics.com.au/tiny-avr-programmer.html

 
Here we are using a 6-pin TPI
The interface is typically used for programming tinyAVR.
 

The 6 pins are MISO, +5V, MOSI, GND, RST, SCK  
It only requires power, ground, data, clock, and a reset pin
MISO = Pin 1 




-------------------------------------------------------------
 
Background to AVR microcontroller pogramming
When AVR microcontrollers were first introduced in 1995, Programming was simple.
There was just one programming method (Serial Programming Interface or SPI).
This used 5 x 2 10-pin target  .
 
There are a few alternative type of  pin targets that I sometimes see.
Common are:


6-pin PDI
The 6-pin PDI is used for programming AVR XMEGA.
This is the programming interface available on all ATxmega microcontrollers,  
It is functionally the same as ATtiny TPI interface and uses the same two pins – RESET for clock and a dedicated pin for programming data.
 

 
6-pin TPI
The interface is typically used for programming tinyAVR.
It stands for tiny programming interface
The devices that use this are ATtiny10, ATtiny102, ATtiny104, ATtiny20, ATtiny4, ATtiny40, ATtiny5 and ATtiny9.
 
 
 

The module below is a Duskwork self-tuning VCO
 tHE red stripe goes to the top --- MISO
 
Links
+ Microcontroller... What you need to program a MCU