Biggest thing I didn't like was the channel 9/19 scan feature. Used a big, fat PROM chip between the channel selector and the PLL. Learned to hot-wire the radio for normal channels only so the channel 9/19 dual watch wouldn't go psycho when it felt like it.
Never did get to the bottom of why it would get twitchy. Could have been the front panel slide switch, maybe. Wasn't worth my while to do the Sherlock Holmes on it, once I worked out the patch to disable it. The drivers just wanted it to work on the channel they chose.
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