VS-MIDI
MIDI Interface for Vermona Synthesizer
Model 8-434 ver. 1.0
Copyright © 2009 CHD Elektroservis
All rights reserved. No part of this publication may be reproduced in any form without the written permission of CHD Elektroservis.
14
d) Now, version of instrument’s VCO board must be identified and in dependence on it, jumper
on interface’s board must be set. Version of VCO board can be easily discovered pursuant type of
operational amp on IS1 position and pursuant values of resistors R24 and R25:
Pic. 2.7-4 – Detection of VCO board version
Older version of VCO board (1) has operational amp B081 (it has 8 leads) on position IS1 and
values of R24 and R25 resistors are 220kΩ. Newer version of VCO board (2) has operational amp
A109 (it has 14 leads) on position IS1 and values of R24 and R25 resistors are 22kΩ. Type of
operational amp is printed directly on its cover and values of the resistors can be measured with help
of a multimeter for example.
For older version of VCO board (IS1 = B081; R24, R25 = 220kΩ), plug jumper on interface board
to position (1). For newer version of VCO board (IS1 = A109; R24, R25 = 22kΩ), plug jumper on
interface board to position (2). See pic. 2.7-5.
Pic. 2.7-5 – Setting of jumper
1) Older version
2) Newer version
1
2
