Attack
and decay time extension
Pulling the "attack" knob
will give you attack of 5 seconds
and decay til 3 minutes.
Press the red button and play a
song !
Pot to replace with push-pull
one :
- "attack"
The idea is to add a 10µF
tantalum capacitor in parallel
with C46 (1µF) on board B,
respecting polarity : - to -
and + to +.
Solder one lead only to a C46's
lead and the other lead to a cable
connected the "D"
lug.
Run a cable between the "E"
lug and the other lead of
C46, so when the push-pull is
pulled, the 10µF capacitor is in
parallel with C46, total value is
11µF.
Twist the cables and use tantalum
caps, electrolytics might not
retrigger.
Same mod can be done for on and
off times, by adding a 22µF
electrolytic cap to C48 (2µF).
Warning - disclaimer
All modifications are at your own risk and I assume no liability for personal injury or damage to equipment or loss of use caused directly or indirectly by the use of any info shared in these pages. Although these modifications are quite simple they should only be performed by those experienced in electronics with access to at least a good oscilloscope and frequency meter, some will need a recalibration of the Synthi. Do not attempt otherwise.
EMS PCBs are very fragile, to avoid damaging the tracks do not use a too hot soldering iron (I set mine to 315°C).
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