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TUCoPS :: Radio :: ic271.txt

Mod for Icom IC-271/471/1271




de DG8FZ @ DB0EAM

How to make the VOX of an IC-271,471,1271 usable for FM :

1'st type of 'main-board' :

The only thing to be done is to add a diode such as 1n4148 or bax13 on the
MAIN board on the position D74
When D74 is inserted ... the vox works in FM also.
The diode is on the shematic diagram of the Main board but
is not mounted on the pcb in the factory.

 73's de stefaan
 ON4BY @ ON4HU
 16/03/1990  18.31 h


2'nd type :  (On this board a D74 is present (near PA- and RF-YGR- Unit))
             (It might be not present in the plans !)

Disconnect the cathode of D69 from it's old postition.
It's new position is the cathode of D50 or D51

 name ! position on main board ! (old) function !
 D69  ! near 'CW-DELAY'.       ! 'FM -VOX-OFF'  ! FM 8V
 D50  ! near 'RF-YGR-Unit'     ! 'USB-VOX-ON'   ! USB8V
 D51  ! near 'RF-YGR-Unit'     ! 'LSB-VOX-ON'   ! LSB8V

 73's de karl
 DG8FZ @ DB0SAO
 20/03/1990   16.52 h





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