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
Pot to replace with push-pull
lug and put a 10µF tantalum
cap on the "F"
lug, with the same polarity
(negative leg). Join both positive
legs with a cable and connect it
to the positive point of C46
emplacement on the board (inward).
Connect a cable between the "E"
lug and the negative point
of C46 (outward).
Of course, 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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