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Icom IC22S Packet Modification The Icom IC22S is a ten watt diode matrix PLL synthesized 2 meter rig manufactured in the early 1970's. In it's stock condition it tunes 146-148 MHz in 15 KHz steps. Since I am sure there are a few of these sitting on shelves collecting dust due to the limited tuning range, why not modify them for the perfect packet rig. First replace the 7.68 MHz Oscillator/Divider crystal (X1) with a 5.12 MHz crystal. This will move the band to 145.00- 146.94 MHz in 10 KHz increments. The repeater offset will now be 400 KHz which should not pose a problem in simplex packet operation. I will give the diode matrix settings for the most commonly used packet frequencies. You can formulate others as needed using the formula N=100*(f-145)+61 and the manual. The diode positions indicated ARE WHERE DIODES ARE PRESENT. The other positions are left empty. 145.01= D5,D4,D3,D2,D1 145.03= D6 145.05= D6,D1 145.07= D6,D2 145.09= D6,D2,D1 73's de Scott N5JLQ @ K6IYK