Hard-Sync ModificationThe SH-2 has two VCOs so it could be used with hard-sync. I use the Wide/Narrow-Tune switch to enable the hard sync. In wide position the hard sync is on, in narrow position the sync is off. The required modification is technically quite easy, but mechanically it requires some skills.
You have to double the circuitry if Q29, R152 and D11, but feed the duplicate of D11 not from IC14 pin 1, but instead from IC 18 pin 7.
Q29 is a J-FET "SK30A QR", wich is out of production, but still available on ebay
D11 is a standard diode "1S2473". You may use a 1N4148 instead.
R152 is a 15k resistor.
I marked the modification in this:
Schematics with Sync-Modification
Mechanically it is required to split the traces under the Wide/Narrow switch and to rewire the connection to the tune potentiometer. See the marking in this
PCB-Drawing with Sync-Modification
A further idea is to split the Bender On/Off switch for VCO-1 and use it to enable disable the autobend for VCO-1, which would be useful with hard-sync.
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