[sdiy] Help with transistor switches

[Plutonique9]

Hello,
Last week I picked up a Zoom Sampletrak Phrase sampler, and, well, 
I've already started to modify it. So far I've had sucsess triggering 
the samples from my 808 trigger outputs buy adding a transistor 
switch across where the sample pad contacts are. This is ultra 
smooth, and necessary for the machine, as the midi input only offers 
"gate" control over the samples, ie. no triggering one-shot or 
re-triggers from midi.... yes, pissed me off this did, but now this 
works excellent because the 808 makes an excellent master controller 
for triggering loops and samples on the SampleTrak. Also, because the 
onboard sequencer only records note data from the onboard pads (not 
via midi), this opens up a more powerful way of inputing data into 
the sequencer.

The switches i built were taken from the doepfer FAQ, instead of the 
switch going to ground though (for the s-trig convertor), it close 
the two contacts of the pads.;

http://www.doepfer.de/faq/gen_faq.htm

So, triggering the sample pads works like that great, however some 
other pads that i want to add trigger inputs to control are not 
working. I'm guessing that this is because the onboard "Sample pads" 
are scanned alot quicker than these other pads, those being non time 
critical, so i'm thinking the transistor switches for these are too 
short. So I need to somehow lengthen the time of the switch a little 
more, so that external triggers are registered. I'd hopefully like to 
avoid any "extra" circuitry, other than passive components, in an 
effort to keep this simple and cruisy, that is unless it is 
absolutley necessary to use an IC (like a 555).

The need for this modification, is to add something to the sampleTrak 
that i enjoyed on my old Roland MS-1. It had a trigger input to start 
and stop the "sampling" recording, and with my 808 side by side, it 
made recording seemless beat loops a breeze, because manually setting 
a loop on a phrase sampler is quite tricky. 

The second trigger input was to trigger the "play/stop" button of the 
onboard sequencer.

So these two don't respond to the same meathod of a transistor switch 
across the pad contacts, as in the doepfer FAQ. So, any way to easily 
extend the time of the switch?

Thanks for any help

Seeya



-- Plutonique9, Plutonique9 at symbiocom.com

http://www.mp3.com/Plutonique9