CLEAR CHANNEL AMATEUR RADIOS:

AR 3300
AR 3500

Frequency Expansion:

• Remove the bottom cover.
• Locate the three pins near the front of the radio
• Solder a jumper between these three pins. Radio now has from 26.000 MHz to 29.999 MHz.

• Turn VR-17 (AM MOD) fully counterclockwise.
• Turn VR-15 (ALC) fully clockwise
• Turn VR-16 (AM POWER) for maximum carrier level.
• Modulate the radio. Tune VR-16 (AM POWER) to achieve maximum carrier and still retain forward movement on the RMS wattmeter. VR-16 can be removed and replaced with three wire leads routing to an external 5K potentiometer for variable power.
• As carrier is decreased, modulation is increased. At 10-Watts dead key using a D-104 Silver Eagle, I get 25-30 Watts peak swing with tremendous modulation.
• VR7 = AM/FM S Meter
• VR8 = SSB S Meter
• VR4 = FM Dev
• VR11 = RF Meter

Cut one leg of D-73 to provide talkback in AM mode.

 
Variable Power Modification

This modification adds variable power to the AR3500. You will need a 5K chassis-mount potentiometer, an appropriate knob for the pot, and enough hook-up wire for three lengths to route from the main board to the outside of the radio chassis. The potentiometer is mounted to the side of the radio chassis, on the left side of the radio as you are facing it (with the speaker down). A through-hole for the potentiometer shaft must be drilled through the radio chassis as well as through the radio covers. This modification will provide variable RF out for AM/FM/CW modes only. The instructions below assume the potentiometer has been installed in the radio chassis.
 

• Unsolder VR-16 (AM POWER) from the main board.
• Solder a length of hook-up wire to each of the three holes vacated by VR-16.
• Install the three loose ends of the hook-up wire to the potentiometer terminals.
• Solder the center wire to the center terminal of the new pot. Solder the other two wires to the remaining terminals on the new pot.