SuperStar 121



+ 10 KHz Jump Switch

1)Get a SPST switch and mount it in the radio.
2)Find IC 6 & 7 by the PLL chip. You will see J25 and J27
3)Solder a wire from one side of the switch to J27.
4)Remove the jumper that is J25.
5)Install a 4.7k Ohm resistor in its place.
6)Solder a wire from the other side of the switch to J25.(see Picture)
5)That's it .Flip the switch to jump up one channel.

Channel Expansion

1)You will need 3 SPST switches and mount them in the radio.
2)Find the PLL MC145106.
3)Locate pin # 10 and cut the trace going to this.
4)Switch #3 will be soldered to the cut traces on pin # 10.
4)Solder wires to the other 2 switches as in the picture above.
5)That's it!

ALl the switches down will give the normal channels of the radio.

With the radio in 'HIGH' band and switch 1 UP , 2 DOWN , and 3 DOWN:

You get 27.845 - 27.955 on channels 10 to 19.

With the radio in 'MID' band and switch 1 UP , 2 UP , and 3 DOWN:

You get 27.925 - 28.065 on channels 1 to 12.

With the radio in 'HIGH' band and switch 1 UP , 2 UP , and 3 DOWN:

You get 28.045 - 28.155 on channels 27 to 38.

With the radio in 'HIGH' band and switch 1 DOWN , 2 DOWN , and 3 UP:

You get 26.135 - 26.575 on channels 1 to 40.

bbs
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