Kenwood ts-430 AGC mod

The type of speech processor circuit used in the ts-430 is an agc (automatic gain control) driven audio frequency amplifier.
By decreasing the time constant substantially, the speech processing effect will be improved.
The modification is very simple.
Replace capacitor c104 4.5 uf on the if board by a smaller value of o.47 uf.
To Modify This Capacitor

1. Remove the if board as indicated for the cw filter installation.
2. Remove c104 from the board.
3. Mount a 0.47 uf capacitor on the board.
4. Mount the if board as indicated by cw filter installation.
5. You are now fully operational again.
6. Adjust the mic gain without the processor until normal alc deviation.
7. Switch the processor on and adjust vr7 near c104 until normal ALC deviation. (do not alter the mic gain at this time)
8. Enjoy the speech processor improvement.

GW1NGL W1NGL Kevin Roberts Ham Radio

Page last updated on 12/29/2011 by Kevin Roberts W1NGL a colection of Ham Radio and Electronic Information