Vintage Simmons Drums (UK) Users Group

Hi Pigletdad40,
if you have a tomcard, it's possible to convert it into a hihat. There are
some empty gaps on the drumboard (card) which must be filled with some
additional resistors, capacitors and diodes. There is only one eprom
responsible for both open and close sounds, the pedal regulates decay of the
vca and triggers also the env generators. The SDS's HH is, by the way, one
of the best playable and sounding HH's available. Open, close, half, chick,
stomp, splash, very nice. Invented 20 years ago...

The SDS5/SDS7 pedal itself is constructed around an infrared interrupt
switch, a H21A1 (Google around for details). It is definately not possible
to use other pedals without modification. The Hihat XLR of theSDS7 outputs
15V on its Pin 3. There is Gnd on Pin 1. And Pin 2 is the input of the HH
control-voltage. Using switch-pedals will result in shortcut of the SDS7
brain.

To increase sampling time, you can modify your new HH-card to 64K and
download the long HH eprom from www.simmonsmuseum.com.

So, if you made your decision to convert a card, I'll give you all details.
Michael