Showing posts with label DIY. Show all posts
Showing posts with label DIY. Show all posts

Sunday, 16 February 2020

Jasper Midi interface - build notes

JasperMIDI is a simple MIDI interface to allow you to connect Jasper or other EDP link enabled equipment like the vintage Wasp and Gnat Synths or Spider sequencer to modern control equipment

If you buy from the manufacturer, you will get a pre programmed ATMega328  microcontroller

"It provides a pretty robust translation from MIDI to Jasper’s Link port, and converts notes on the Link port to MIDI enabling Jasper’s touch keyboard to be a very limited 2 octave controller."


i'M building this for a friend and he hasn't chosen the type of case the Jasper will be housed in.
This choice is impt as it will dictate how we power it, what voltage regulators are needed , and what connections to use.

"JasperMIDI has an optional 5V regulator allowing it to be powered with a 6V - 12V supply, or this can be left out and it can be powered using an existing regulated 5V. It can also take power over the Jasper mini DIN connector."

The PCB uses a MCP1702-5002 5V voltage regulator TO-92.
So this can be left out if powering from the Jasper main board.


I think the last and first options are out if it is to be installed in the case.

"If you built Jasper with a case including a speaker, then there will be enough room to install JasperMIDI. You can omit soldering the mini-din socket, and the power regulator components. Use hookup wire or ribbon cable to connect JasperMIDI to the Jasper main board. Use the 5V header
on the JasperMIDI PCB to the 5V pads (or connector) on the Link2 header."


Links:
+ Jaspersynth
+ Jasper Midi

Wednesday, 12 February 2020

Jasper build notes - Part 2

This is part 2 of my Jasper build.
Part 1 is here.
https://djjondent.blogspot.com/2019/11/jasper-wasp-build-pics.html
The Jasper a a very very close version of the EDP wasp synth.
I have a couple of vintage ones so I'll try to calibrate this one as close as I can to the originals.
The originals are so fragile (and too expensive) to take outside the studio. Thus I'm building one Jasper for myself to gig with, and one for a friend.

This is where I left off in Nov 2019:


I had a lot of trouble finding the correct pots.

esp the double gang 1M.
The Mouser and Ebay  ones i bought were all the wrong size.

Small Bear is the place to get them.

 The pots need to mirror their PCB outline, or they wont slot into the faceplate correctly
 You will probably need to bend leads.

Avoid shorts at all costs,  .... use heatshrink



The BOM uses 17mm spacers. If the legs of the pots aren't long enough extend them with spare wire.
Be careful if you are bending them as they easily break.


tHIS is the reverse log pot. It's labeled C1M.
Almost there
Lining up the pots with the faceplate is tricky




iT'S time for the 9mm mix pots and the hold switch.
+ Potentiometers - Basic info for DIY

The Mix pots consist of Oscillator 1 & 2 volume controls and the external audio input.

Osc 1 & 2 use 50K log
Solder 3 wires to the pot


The ext audio input gain is a 100K log pot.
 "only solder 2 wires to the pot – this is used as a variable resistor in the gain
circuit of the input amplifier.............. as there is a 3 pin
header on the PCB – the third conductor is for a shield or gnd wire"

The Hold switch is a sub-miniature On-Off SPST or a DPDT on off on

"you have a choice when wiring up the Hold switch. There are two hold variants on the PCB:
•S8 Hold1: This holds the envelope open, and allows use of the Envelope repeat function.
•S9 Hold2: This was the hold feature on the v1 Jasper PCBs. It prevents the envelope from decaying. 


It's quite nice in that you can switch it on without playing the keyboard, and the hold only comes on when you hit a note. However it prevents the VCA repeat function from working.
If you're using a single SPST on-off switch, then you probably only want to wire it to connect to the S8 Hold1 header.
If you want to use both hold variants use a sub-miniature DPDT on-off-on toggle switch"


I'm using a DPDT


The Ext Trig Mod header connects to a switched jack socket.

The tip connection is marked as T, the switched is S and the ground/sleeve connection is G.




Decided to solder the pots direct to the PCB

Almost there..... powers up

to be continued........................

Links:
+ Jaspersynth
+ BOM
+ Build notes
+ DSL man.de
+ Knobs
+ Elby Knobs 
+ Potentiometers - Basic info for DIY
+ Muffs 
+ Muffs - 1 
+ Muffs - Build thread 
+ Buying Jasper
Mouser cart
 

Friday, 7 February 2020

NLC Motherload for 2020

This should keep me out of mischief during 2020
Andrew was pretty busy with new modules last year.


 Mobius PiLL
Dual LFO/VCO
1U Signum
VCAs
Beat Freq
1U 6HP Difference Rectifier
Cellular Automata
1U Sloth Chaos
Dispersion Delay
DelayNoMore 3
Bi-di Choppers
I can't believe it's not a VCO

Some NLC words of wisdom:






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.




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

 ------------------



 + 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.

---------------------------
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.


---------------------------------------
to be continued................. 
Part 2 is here

Thursday, 30 January 2020

Noiro-Ze VCF & VCA

These are my build notes for the Nonlinear Circuits Noiro-Ze VCF/VCA



This looks like a fusion between the VCF based on the Steiner-Parker diode VCF and a Korg PS3100 VCA.
The the Steiner diode VCF uses diodes of course, but Andrew has substituted LDRs.... you are basically
making vactrols. You will build a light proof box on the PCB.

The original Steiner filter is so very different from all the other filters that I've used. I first heard this on my Arturia Minibrute.  According to Vintage Synth, it can self-oscillate like the Minimoog, but has an opposite polarity so it doesn't lose any volume when resonance is increased



"The nice thing about this filter is you can feed different signals to the LP, BP & HP inputs then 
surf between them with your CV, quite different from regular filters."



"issho ni karaoke ni ikou ka:
 translates to
Let's go out together
 
karaoke (カラオケ) is a Japanese word. 
It's a blend of two words — kara (“empty”) + oke (short for “orchestra”).  

I'm using 2n2 capacitors for the LDRs.


tHE 180K resistor is here

RL resistor -- 10K

Headers to connect the two PCBs
A bit fiddly. Start with the vactrol box


"You may need to adjust the 2n2 capacitors to suit your LDRs. For GL5516, 2n2 are
fine. For GL5539, which has a higher on-resistance, I found 1n caps worked well." Andrew F


I'm using GL5549 LDRs ... so i may need to tweak the capacitors.
I'm starting with 2n2 for now.





I'm using all b100K pots.
So the top 3 will need the log conversion treatment.



Sounds great !!!


Another finished NLC Module. :-)



Links
+ NLC Blog
+ NLC Wiki
+ Module Info - wiki
+ BOM & Wiki
+ YuSynth Steiner VCF
+ Ken Stone's Synthacon VCF
+ Build notes for the CGS synthacon VCF
+ Potentiometers - convert Linear to Log

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You can find more NLC builds here.
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