During the 1970’s, Japan produced the classic ICOM IC-22 FM transceiver. Pretty well all of us had one of these, or something like it, in our cars at the time.
Recently, I was poking around in the garage and came across my old IC-22 FM transceiver. Still works, sort of. Unfortunately, these old models did not support CTCSS (PL) tones which most modern repeaters require for access.
During the 1970’s, hams adopted 2 meter FM in a big way. We migrated from large, heavy surplus commercial gear to smaller solid-state rigs, mainly from Japan. Much of this decade was dominated by the very popular ICOM IC-22 FM transceiver. I used these as both base and mobile radios, as they mounted easily under the dashboard.
There were actually several variants of this radio. First was the original IC-22 which was noted for a very solid front end with a helical resonator filter, and used phase modulation. A few years later, the IC-22A arrived (shown above) with true frequency modulation and an improved transmitter. You could vary power output between 1 and 10 watts.
Most 2 meter rigs at the time were crystal controlled. Both my IC-22 and IC-22A needed crystals to operate across 22 channels. In the late 1970’s, ICOM changed these radios to work with a frequency synthesizer. The IC-22S was a unique design providing a diode matrix board. By inserting diodes, you could program the PLL divider using BCD set by the diodes.
In the 1980’s, ICOM took this a step further by mounting BCD thumb-wheel switches on the front panel. This variant was the IC-22U or IC-24E in Europe.
ICOM IC-22 FM Transceiver when the bands were hopping
Back in the 1970’s you could get a ton of use out of your ICOM IC-22 FM transceiver. You had constant activity on two meters, both repeaters and simplex. Pretty well every ham had one of these radios in their car and rush hour ham activity was massive. Typically, you would make contact with a friend over a repeater and then move to a simplex channel.
A very popular feature at the time was repeater auto-patch. You could use your 2 meter radio to make personal phone calls by just attaching a DTMF tone pad to the microphone. These worked well but of course were without privacy. On the other hand, it was a way to get your spouse on the air!
You can see my old IC-22A sitting on top of my modern Yaesu FT-2800M in the shack. The Yaesu is synthesized and quickly scans all the channels. But hardly anyone uses two meter repeaters any more. I can spend the whole day scanning and hear very little.