To allow "normal" transmitter power above and below 144-148 MHz. Short the CI-V line of the CI-V jack on the back panel, to ground.
Push and hold the RIT and Sattelite keys whilst turning on power.
Push 9 key to enter the expanded frequency power set mode.
Enter the adjustment mode for 144Mhz out-of-band RF power. A wattmeter must be connected.
Push RIT key to transmit 145.01 automatically. Then rotate the tuning knob to adjust the desired RF power.
Push RIT key to memorise. Similar for the 70 and 23 cm bands.
Note that the transmitter power does drop off below 140/425 MHz, and care must be taken not to keep the transmitter keyed in FM mode for long periods as the transistors get hot working into a out-of-resonance stripline.
If the band 136 - 140 is going to be used frequently, then a small adjustment of C659, and the fitting of an additional trimmer capacitor, 5 - 25pF at the antenna end of L657 to ground, and adjusting for max power at 138MHz, will reduce the strain on the PA transistors.