Page and personal memo about electronic music, vintage music electronics, DiY, repairs and other geeky stuff.
If you are here for Synthesizer and Studio electronics repairs and servicing please move on to the Synthesizer and Vintage Studio Electronics Repair Service Page.
New project added: (07/01/2012)
This Midi to Trigger interface generates a TTL (5V) trigger signal per note over a range of ten notes. It can be used for example as a midi interface for vintage drum-expanders or as a multiple-trigger generator for a modular synthesizer.
New project added: (04/01/2012)
Tama TS305 Midi Trigger Modification
The Tama TS305 drum-expander, which is a great sounding machine but unfortunately totally lacking of midi control.
Newly fixed: (19 nov/2011)
TR-808 Handclap circuit repair/BA662 replacement
TR-808 needing repair.
TR-606 power supply repair and switch replacement.
TR-606: Repair done.
New project added:(01 nov/2011)
DC-DC converter based bipolar power supply for effect units and portable devices.
Some circuits require a bipolar power supply. In a portable unit like an effect pedal, that can sometimes be troublesome, since it is likely that we want to power our effects with a standard 9V or 12V wall-wart or batteries and don’t like the idea of putting an AC mains transformer plus rectifiers and filtering into our boxes. That’s where a Dc-Dc converter based circuit can be an alternative:
DC-DC converter based bipolar power supply
Midi-CV/Gate converter now commercially available from Pittsburgh Modular:
I am proud to announce that my Midi-CV/Gate converter is now commercially available from Pittsburgh Modular in a standard Eurorack format. This is great especially as it ‘s being sold at a very competitive price and comes completely assembled and calibrated. Of course the code and schematics will stay available at this page for the DIY community. Check out the link to Pittsburgh Modular.
Pittsburgh Modular Midi-CV/Gate Interface
Project Updated: (01/10/2011)
New firmware version for the Midi-CV/Gate converter. The new firmware allows CC Controller assignement and individual CC Midi channel selection.
Midi CV/Gate converter
Lately repaired:
TR-909
Another TR-909 for repair on the Bench. This is actually the 4th TR-909 I am repairing!
It came with a problem on the bass drum ‘Attack’ parameter, turning the knob wouldn’t do anything. I thought this would be an easy one and a good cleaning of the potentiometer would cure the problem but not so…
TR-909 Inside
Project Udated:
Korg KPR77 modification
Due to popular demand, I published the list of changes I did to my Korg KPR 77.
KPR77 Extension Box
New Project added:
Optical Turntable Sequencer
A tangible sequencer with midi output.
Turntable scanner and black felt dots.
Newly Repaired:
Korg A1 Signal Processor
I just found my Korg A1 in my processor rack being mute. No signal coming out whatsoever.
Project Updated:
Wifi Router Webradio
Wrote a new Interface script which allows to display a menu of all preset radiostations. By sending ‘MENU_’ over RS232 to the router, the display will now show the current station, any ‘BUTTON_’ command will cycle through the preset radiostations. One more ‘MENU_’ command will select the current station and start playing it.
This way, the station selection is performed in a much neater way than previously with the Up/Down controls. The new script can be found in the project zip file and is named ‘interface3.sh’.
Link to Webradio project.
PIC16F628 based LCD display driver
Controllable via serial data input and with a 4 button command interface.
- Picture of the finished display
This is a serial data LCD display driver I developed to be used in conjunction with Jeff Keyser’s Wifi router webradio project. In order to get this display driver working together with the router, see the interface related shell scripts for the wifi webradio here.
The driver is laid out to hook up with a 2×40 LCD display but could easily be adapted to suit other displays by adding a scrolling functionality. Right now I did not add this feature due to the lack of such a display for testing.
The main features of this driver are:
- Works with common HD44780 based LCD displays.
- Serial Input, only 4 wires needed (Rx, Tx, Vcc, GND).
- User selectable baud rate (9600 or 19200).
- 4 Button – Interface with user definable message output and counter value output.
- User-programmable splashscreen message.
- User-programmable start message to avoid display from showing boot-time messages.
- All user definable parameters are programmable via serial port commands, no pic programmer required.
- User definable parameters stored in EEprom.
How to make Frontpanels using Lazertran decals.
PIC16F628 based Midi-Sync/Sync-Midi Converter
Midi to Sync/ Sync to Midi Converter Schematic++ © Obsoletetechnology 2009-2011 ++ all Rights Reserved ++
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