FrontPanelDesigner and HPGL

If you are designing frontpanels with FrontPanelDesigner (https://www.schaeffer-ag.de/en/downloads/front_panel_designer/) as I am, here you have instructions how to save about 50% in the costs with grouping and HPGL. In my Prodigy-panel most of the engravings are done with 0.2 tool. The lines and bigger texts use 0.4 tool. Normally every engraving creates a new object, so your panel has many objects and the factory charges by objects. It's possible to group similar engraving objects to one HPGL-object, so eventually you have only two engraving objects (one for 0.2 and one for 0.4 tools) and the drilling holes.

1. When I am ready with the design, I save the design in FrontPanelDesigner to another file named Prodigy_tool02.fpd where I leave only the 0.2 engravings and delete all the other stuff. I also save the design to Prodigy_tool04.fpd file where I leave only 0.4 engravings. Third file that I save holds only all the drill holes. Make sure the origin in all these files is in the lower left corner!

0.2 engravings

0.4 engravings

drill holes

Here is the end result!

2. Export the tool02 and tool04 files to DXF files. Do not export the reference points!
3. Import these files to some CAD-tool that can read DXF-files and create HPGL-files. I use the free CadStd Lite-program (http://www.cadstd.com/). In CadStd I leave only the gravings layer active and export only visible layers to a single pen HPGL-file.
4. In FrontPanelDesigner I open the drill holes file and select insert HPGL engraving. This activates a crosshair tool with which I click the origin (X:0.00 Y:0.00). Select the tool02 HPGL-file, set the tool to 0.2 width, select the color and click "Origin of HPGL file" and OK. Then I repeat this with the tool04 HPGL-file.
5. If you want to save more you can leave the in-fill color out. With this black panel the colorless engravings look very good. You can fill the engravings afterwards manually with Lacquer-Stick paintstick color from Micro-Tools (it is little bit messy but it works) http://www.micro-tools.de/en/Paint-oxid/Lacquer-Stik-Paintstick-White.html

Panel is ready!

Yamaha V50

I bought this synth as a new in 1989. Now the internal battery reported it is dead and it needs to be changed. I new that all the internal sounds will get corrupted in this operation. That's not a problem because there was only one sound that I had programmed. Here is a picture of the main-board where you can see the yellow CR2032 battery. The other picture shows my V50 together with analog-friends SH101 and TTSH2600. I think now I am ready to program more FM-sounds. I have the book "FM Theory & Applications" by John Chowning and David Bristow and the original operating manual for V50. Now I must just start to create new sounds.

Prodigy Eurorack Modifications

Here are more detailed instructions on how the modifications are implemented. OSC IN and VCF IN are alredy in the original PCB so they need no instructions.

OFF-position is the original connection. ON-position connects +12V thru R188 to R131/Q39 and opens the 3080 VCA.

When using the KYBD IN V/Oct input you must connect the JUMPER CABLE (see also earlier building instructions in my Blog) so that the KYBD IN is tracked all the time. Leave out the R82 resistor and C23 capacitor. RKYBD replaces the external resistor network.

GATE IN goes direct to R153 resistor. If you are using the original keyboard then GATE OUT must be connected to GATE IN.

Contour Sync OFF-position is the original connection where +12V is connected to Pitch Wheel resistor R180. ON-position replaces this +12V with filter envelope output. When Contour Sync is ON the Pitch Wheel acts like an attenuator where you can choose how much the filter envelope changes OSC2 pitch. When OSC2 to OSC2 Sync switch is ON and this Contour Sync switch is ON then you can change the Sync-sound with filter envelope and Pitch Wheel.

R41 and R48 are both 10k for symmetrical Square. R41 goes direct to +12V and external PWM-input for OSC1 goes between these two resistors.

OSC2 is identical to OSC1 but there is also the R184 potentiometer which adjusts manually the OSC2 pulsewidth.

RIP Don Buchla

Synth pioneer Don Buchla has died at the age of 79. Good news is that his heritage is living strong. Composer Suzanne Ciani played with Buchla instruments in 70's and became a good friend with Buchla. Here this heritage is transferred to younger generation when Ciani plays with Kaitlyn Aurelia Smith in their Sunergy project.

Synamiitti 2016 in Turku

I was showing my DIY Moog Prodigy-clone at this years Synamiitti in Turku. Small place but full of synth-stuff. It is always nice to talk with other synth-builders and people that are interested about synths.

The modular corner.

DIY four voice Roland Jupiter.

My Eurorack Prodigy and it's big brother MiniMoog.

Nice DIY MOTM-size modular.

Electric Druids MIDI2CLK

This is my version of Electric Druids MIDI-to-analog-gate-pulse project (http://electricdruid.net/midi-clock-to-analog-gate-pulses/). I programmed the PIC16F688 chip and build this prototype board. It works great. From one MIDI-clock you get two separate analog clocks with adjustable division rate. I noticed that when you change the clock division this chip loses where is the first beat. To correct this you must stop and start the MIDI-clock. This is not a problem for me because I use this module just to convert the MIDI-clock to analog-clock with no division rate at all. I can easily create those different divisions with my Abstract Data ADE-32 Octocontroller (http://www.abstractdata.biz/products/eurorack/3x/ade32/) which is little bit smarter and handles these division changes seamlessly.

Karelian Skies 2016 Full Concert

Here is the full concert video from this years Karelian Skies!