Voltage Controlled Divider modification.
2002-01-22 by sasami@hotkey.net.au
While looking through the EGRES (Serge) web site, I noticed they have a
similar module to my Voltage Controlled Divider. I frequently refer to mine
as a Divide by N in my own notes, and this is almost what theirs is called -
Divide by 'N' Comparator (NCOM).
There was one significant difference between mine and theirs - they also
provide an output derived from the internal staircase generator. As mine
also has this, it was an obvious thing to do, but didn't occur to me for
some reason or another. (Maybe I'm just thick!)
Anyway, adding such an output is really easy. A buffer made using an op-amp
wired in the classic input follower configuration, and a 1k output
protection resistor are all that are needed. I've added the components to
the schematic in grey, so the modifications are obvious.
It is worthwhile.
The CV input selects the number of steps the staircase will climb before
setting to the beginning. With the output of the saircase generator fed to a
VCO, feeding the CV input with a ramp signal gives an interesting effect. It
could possibly also be used to synchronously switch through tables in
something like the mini-wave, where the wave is selected via a CV.
Ken
_______________________________________________________________________
Ken Stone sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>
similar module to my Voltage Controlled Divider. I frequently refer to mine
as a Divide by N in my own notes, and this is almost what theirs is called -
Divide by 'N' Comparator (NCOM).
There was one significant difference between mine and theirs - they also
provide an output derived from the internal staircase generator. As mine
also has this, it was an obvious thing to do, but didn't occur to me for
some reason or another. (Maybe I'm just thick!)
Anyway, adding such an output is really easy. A buffer made using an op-amp
wired in the classic input follower configuration, and a 1k output
protection resistor are all that are needed. I've added the components to
the schematic in grey, so the modifications are obvious.
It is worthwhile.
The CV input selects the number of steps the staircase will climb before
setting to the beginning. With the output of the saircase generator fed to a
VCO, feeding the CV input with a ramp signal gives an interesting effect. It
could possibly also be used to synchronously switch through tables in
something like the mini-wave, where the wave is selected via a CV.
Ken
_______________________________________________________________________
Ken Stone sasami@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>