Monday 8 July 2024

MUN - build notes 2

 This is part 2 of my build notes for the nonlinear circuits Mun module.

The eurorack 22HP module is a 10 channel vocoder based on the Syntovox 222

The word Vocoder is a combination of two words.
Voice + Code = Vocoder
Vocoded signals were essentially a form of data compression for voice.


Part 1 is here:

To be continued....

Monday 1 July 2024

Gaggiuino - boiler & pump removal & first tests - part 6

These are my personal build notes for building the Gaggiuino espresso machine.
I'm not a part of the Gaggiuino team.
The project is not for profit. 

This is really fun if you're interested in learning how microcontrollers such as the Arduino 
can be applied to solving a daily problem of mine ..... how to consistently make a great cup of coffee.
The Gaggiuino team have come up with a solution for modifying a relatively inexpensive coffee machine into something amazing.
This particular modification uses a STM32F411CEU6 (BlackPill) microcontroller.

Part 1,2,3,4 & 5 are here:
   Part 5 Gaggiuino - wiring

The build might change as I work through the various issues which will obviously happen.
I'll update as I go along.
Gaggiuino Project Page

I've decided to do a custom rewiring.
So I think I'll need to remove the boiler.

Removal of the boiler & pump will make things easier
 to get to the connectors.
You can also remove the 20 min timer PCB while you're at it.

First number all the connections before you disconnect anything.

The single boiler has two heating elements. 
They are connected to 1,2,3,4.

5 & 6 are connected to the steam thermostat.

Pop out the switches . label them of course. 

Power, Brew, steam
I'll need to remove the switch housings later.

I'll also need to remove the thermal fuse (thermafuse) from  the top of the boiler.
The fuse cuts power off to the machine.

Next remove the steam wand.
The screw in the container belongs to the therma fuse bracket. It holds the fuse against the boiler.

The machine is looking a lot less cluttered and easier to get into
The boiler is just held in place with 4 Allen head screws

Making the T-junction hose

These hose clamps are the best .... They only need a screwdriver to tighten.

The other end of this hose connects to the Pressure Transducer. (0-1.2 Mpa, 5V, G1/4)

You need to cut the orange hose and inset the T-junction
Remove the pump first to make this easier (see below)

As I got deeper into this project, I started to remove more and more cables.
In the end, I removed everything,....  even the boiler and pump. 
It really wasn't so hard.

The pump

To remove the pump
I first removed the power socket.

The pump wiring circuit.
This is the longest (and most confusing) section of cabling.
I left the original Gaggia cable that was attached to the pump (at the pump fuse), and extended one end
to AC on the PCB & the other to the neutral Power Socket. This cable already had the LAMPS attached. I had to extend it further and add extra cabling for the boiler & SSRs.

There is a Allen screw you need to loosen
which sits right under the socket terminals.

If you have a long necked Allen screwdriver it 
will be a breeze.

The other screw has a Phillips head.

You don't have to remove the other Allen screw to remove the pump.

BTW, this also removes the 20min timer circuit which is housed in the black box next to the pump.

The Gaggiuino doesn't use this board.

You can now easily access the pump connections.

The old fuse

The new resettable fuse. 185 degrees C. 16A, M4

Oh dear....the time of reckoning is approaching.
The white hose hanging over the edge of the Gaggia in the pic below, is connected to that "T-junction"  inside the machine. It's other end connects to the pressure transducer which "talks" to the Blackpill microcontroller, relaying info about the pump pressure.

In the end, I did a full custom wire installation. This wasn't my intention in the beginning.
I ended up using most of the cables that came with the Gaggia and just a few that came with my Peak kit.
I've never done anything like this before, but its pretty straightforward if you study the circuit diagram carefully. Always double check the connections.

Nothing has blown up so far :-)
The Gaggiuino is now stabilising boiler temp. Aim is 93 degrees C

This shot is using the default setting

I'm really impressed.
Tastes great. !!!!!!

15g in, 34.9g out, in 33 secs
The weight out is estimated.
I haven't attached scales yet.

Steam test
Wow ... this is a huge improvement on the original Gaggia Classic.

I've ordered some printed parts .
(official supplier)
Can't wait till they arrive so I can install the screen and PCB properly.
What a satisfying build. I can't recommend this enough.

+ Gaggia Classic Evo Pro - Modding with arduino - Gaggiuino
   Part 2 Gaggiuino V3 - Build Log Notes - switches, PCB
   Part 5 Gaggiuino - wiring
   Part 6 Gaggiuino boiler & pump removal & first tests

Monday 24 June 2024

KOLOR - Combining multiple LED tiles

 Some videos showing examples of how to combine mutiple LED tiles

Here is what the rear of the tiles looks like.

There are 3 connections ... 5V, Gnd and either DIN or DOUT

I'm just playing with the random settings on the KOLOR module.

It's Eurorack, from Elk Elektronik's in Australia.
Ed has been working on this for ages, and is releasing it on Kickstarter.
Ed describes it as a WS2812 LED Pixel Strip Controller for Eurorack.

It's compatible with multiple LED strips.

Control can be either manual (via the knobs) or CV patched into 6 jack inputs.

The controls are:
1. Red /hue
2. Green/saturation
3. Blue/value
4. width
5. pixel number
6. preset pattern

For more info visit:

NLC - More (cowbell drum module) - Build notes

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

This module contains three individual cowbell circuits based on those in the Roland TR-808.


As far as parts go there isn't anything rare or hard to find.

CD 40106 
& three Opamps - TL072

CD40106 (CMOS IC with 6 Schmitt trigger inverters)

The really cool thing about this circuit is that it uses a logic chip to make metallic noise

Each bell uses 2 of the 6 oscillators.
I think in the 808, similar circuits provide the basis for the cymbal & hi hat sounds

The original 808 used band pass filters to remove the upper and lower partials.

Andrew's description is as follows:
"The filters are fixed as per the original design. This means the output
is loudest when the oscillators are set close to the operating frequency
range of the filters and softer when the oscillators are at much higher
or lower settings. For me, this seems fine, but mess with the filter
values if you like. I have seen some mods of the 2k2 to ground resistor
varied to change the filter range. In proto-typing, this was
experimented with but I didn’t feel it was much improvement."

resistors next

Diodes: LL4148

These are the power protection voltage rectifiers... or just use a 10 ohm resistor and dont plug the module in backwards.

You'll need a through hole +5V 100mA voltage regulator : 78L05. 

power header

Transistors : BC857, 847
Six 1M pots.

12 sockets

The accent input is tied to the trigger input via the switch tab,
probably best to use a gate rather than a trigger to get the sound going,
but that depends on what you want to do. Otherwise patch whatever you
like to make things happen.
This is a dense but easy build.

More links

You can find more NLC builds here.

Friday 7 June 2024

Gaggiuino -part 5 - wiring

This is part five of my Gaggiuino project.
Basically this adds a microcontroller to a relatively cheap coffee machine.
The earlier parts are here:
At this point I'm just breaking down the wiring and reading the schematic.
I often find I absorb info better if I write things down. Thus this blog.
And hopefully, it will help someone else doing this awesome project.
I am not part of the Gaggiuino development team so there may be mistakes here.
Do let me know if you find any. 
I have a 240 V Gaggia classic pro evo
And I'm using an official PCB from Peak in HK
I bought the kit with lots of parts to get this job done (hopefully with little fuss).
Though, you will need more cables, basic soldering skills & some patience.

Peak Coffee:
The official project page is here:
The discord page is also useful:

There are two important pics you need to digest to wire things up.

The first time I saw the pic below I was at a loss to see where things started or ended.
I'm familiar with electronics schematics, but the mix with hardware is new for me.
But its actually not too bad once you study it, compare to the schemo and work out what the labels mean.
Remember you are playing around with high voltage (240VAC), low voltage DC and hot pressurised water.
So be very careful.

If you've got a different machine, things will be a bit different, but hopefully not by too much.

The code goes something like this :

G = ground

3WV = 3 way valve
the 3 way valve has 3 terminals.

Socket N = 240V power Neutral socket
Socket G = 240V power Ground socket
Socket L = 240V power Line socket

The brass 57 solenoid has 3 flat spade connectors
G = Gnd
L = Line
N (blue) = neutral

keep in mind that there is a difference between high voltage & low voltage cables
(HV use Crimped 6.3mm Terminal Connectors, 30-50cm AWG 22 cables )

Here is the schematic. Try to unite this in your mind with the pic above.
I think I'll start with the 240v socket
(these are the pink boxes).
These connect to Neutral, Line & Gnd.
Socket N = 240V power neutral socket (blue in the schematic)
Socket G = 240 power ground socket
Socket L = 240 line socket
These need to be the thickest gauge wire as they are carrying the highest current

The Solenoid

The brass 57 solenoid has 3 flat spade connectors

Its also know as the 3 way valve in the schematic.

3WV = 3 way valve

the 3 way valve has 3 terminals.
3WV N = neutral (blue)
3WV L = line (yellow)
3WV G = gnd


these yellow boxed ends connect with the PCB

3-out ( to 3WV L)
P-out (to Pump L)
L-in (to the SSR)
N-in (to the pump fuse, pump N, etc)

all connect the PCB to the  outside world.


The vibratory pump

It looks like it has just 2 terminals (Pump Fuse to Pump N 
& Pump L).
These connect to N  & P on the PCB.

grounding wires

All green wires.....   start at the 240V power socket (socket G) on the right
and work left  (frame - 3 way valve - boiler ) to end at the cup warming plate on the extreme left.

The SSR (Solid state relay)

A solid state relay (SSR) is an electronic switching device that switches on or off when an external voltage (AC or DC) is applied across its control terminals. They serve the same function as an electromechanical relay, but solid-state electronics contain no moving parts and have a longer operational lifetime.

It has two sides.
A high voltage AC side and a low voltage DC side.
The AC side connects to the coffee heating elements. 
The DC side connects to the PCB.
It basically translates between the two.

Both sides are isolated (even though they can communicate with each other) using LEDs and phototransistors.

What the SSR does is listen to commands from the microcontroller. 
If the microcontroller sends low voltage digital info to the SSR (say
to heat up the water), the SSR will carry out the command on the high voltage AC end.

It looks like the left AC out from the SSR 
connects to the thermofuse, 
or the resettable fuse 
& one heating element

I don't think you connect it to both.

+ Gaggia Classic Evo Pro - Modding with arduino - Gaggiuino
   Part 2 Gaggiuino V3 - Build Log Notes - switches, PCB
   Part 6 Gaggiuino boiler & pump removal