Disconnect pin 3 of prescaler IC (MB504) from board.
On PLL IC (MC145152), cut pin 4 from ground and connect to pin 3 (VDD). Cut tracks on pins 10,21,22,23,24 and 25, so the connections can be swapped with jumpers as follows:-
Move connections from pin 23 to 21, from 21 to 22, 22 to 24, 24 to 25 and 25 to 10.
Temporarily connect pin 23 to ground. The radio should work as normal on original channels if everything is done correctly. Add a switch or change one of the existing swicthes to disconnect pin 23 from ground . This will lift every channel up 12.5 Khz changing channels 1 to 40 to channels 41 to 80.
RV1 should be adjusted for narrow deviation TX.
73
Jeff
On PLL IC (MC145152), cut pin 4 from ground and connect to pin 3 (VDD). Cut tracks on pins 10,21,22,23,24 and 25, so the connections can be swapped with jumpers as follows:-
Move connections from pin 23 to 21, from 21 to 22, 22 to 24, 24 to 25 and 25 to 10.
Temporarily connect pin 23 to ground. The radio should work as normal on original channels if everything is done correctly. Add a switch or change one of the existing swicthes to disconnect pin 23 from ground . This will lift every channel up 12.5 Khz changing channels 1 to 40 to channels 41 to 80.
RV1 should be adjusted for narrow deviation TX.
73
Jeff
