CEM3310s for sale

[sasami at blaze.net.au]

>>... and there was roland discrete vcadsr in JP4 or 
ProMars...
>
>This uses a high frequency clock with about a 5% duty cycle 
to control a
>switch which discharges or charges the timing cap. The 
frequency varies
>from about 35KHz to about 1MHz depending on the time 
chosen.

This sounds rather similar to a proposal that was printed in 
Electronics Australia magazine in 1976. This article 
outlined an alternative to the "repeat everything for every 
key" approach that was used in organs at the time. Keyboards 
were scanned using a processor, and notes sent to one of 8 
or so PDOs (programmable digital oscillators). The envelopes 
for each oscillator were controlled by varying pulse trains 
to envelope generators that were based on several gates.

Nothing new there now. A lot of things in the article have 
been done for years now in both organs and polysynths.

What I have considered on several occasions since is that it 
shouldn't be too hard to produce a voltave controlled 
envelope generator using an appropriate PIC chip. Maybe 
someone on the list has already done so.

Ken