Saturday, 19 February 2011


i use 1.5 metre multicoloured 8 way jack to jack snakes that i bought from Turnkey in the UK (who are sadly no longer around.. boo!). ive also recently started using George L's 1/4 inch jack connectors on standard RG59 cable. they are expensive but super high quality, look great and they mate with the coax cable very securely, and seem to give a better video image. the multicoloured looms are good for patching up all the RGB signal paths to the converters from the synth and i also use it for the H/V sync signals. the george ls stuff i use for all the rest.
be seeing you

Power supplies

the PSU is the most important single part of any electronic design. i use a Power One module. the spec is +/-12 volts at 2.5 amps. it runs alll my modular equipment no worries. its also a linear design rather thatn a more modern switched mode supply. a switchmode supply from an old PC might work, but i havent tested it.

ill edit this post a bit later with links to the prower one site and the unit i use. otherwise, there is always Google.

updated 8th march 2011 : It appears that Power One dont make linear power supplies any more. theyve gone all green instead. oh well. find or build a Bipolar 12 volt psu that gives you about 2 amps or more of VERY CLEAN power.

be seeing you

Friday, 18 February 2011

An Actual Progress Update

Wow! New News!
1. i met up with Chris from the Video Circuits blog for a Vid-Synth jam. he had his (wicked) Chromascope and an ave-5, i had my modular and my ave-3.  we Did Stuff, and Had Fun. and learned some more cool stuff about our gear.
2. this inspired me to take a new look at the Oscillators. i looked at some captures of my original prototypes, that are based on Moog oscillators. the waveforms were much prettier and they didnt seem to suffer from any of the sync problems that the Sandin 8038 based design can, where they reset in antiphase randomly, giving an effect a bit like interlacing (which is cool, but not always desirable). So i went back to the original prototype and tried a mostly discrete design, based on a transistor array and some op-amp buffers. works lovely, looks lovely, no sync issues. the circuit is actually an EFM design, based on VCO4d, for anyone who remembers that far back in time. i miss toms stuff. there was the occasional discrepancy in the docs but it was cheap, interesting, and available back in the days before the current euro-rack modular revolution.. anyways. Here is a link to Fonik's repository of EFM related stuff. he has a very good site, and his synth looks amazing...
3. im working on a schematic for the new osc. theres nothing proprietary in it. its the VCO4d design, with the timing cap ( C4 on the schematic) changed to 250pF and the 100k resistor on the output of the Saw and square waveform changed to 1k. the pulse waveform doesn't seem to work at these speeds. i am still debugging....
4. i will post some vids. this stuff is fun...
5. I have done some more work on the Mixer Matrix. its almost ready, but still has one major bug with the Bias pots that i need to address on the PCB before i publish the design.
6. I have done some more work on the SPG processor. it still seems horribly temperature sensitive though, so investigations are proceeding.
7. coincidentally, i now have a brilliant Cat. he is stripey, likes watching TV, has big feet and a looooong tail and his name is SPG.
8. Im at the building stage for the Joysticks and the Camera/ external input processor. i will draw schematics once ive built them....

none of the above have schematics yet, theyre all still in my head. i should probably write them down somewhere...

be seeing you.