This is a MOTOROLA IMTS RadioTelephone alike to the one my father had installed first in 1962 and in a series of Buick’s and Cadillacs until 1987.
Owned his own business so the cars + telephone owned by that company.
Head unit in car. Main unit in trunk (single tube and an unending amount of transistors & solid-state under that cover). Antenna was a base-load whip about 4’ tall. Mounted behind rear glass on passenger side. (Was often asked in late 1970s if it was for a CB).
Calls were first operator-assisted, and later one might have to wait for one of the three channels available in Dallas in those years (Dad would irritatedly cuss the rich oilmen who would tie up the lines calling their girlfriends after 5:00 as this was, literally, the only private phone use they had).
Long distance was always operator assistance. Relayed.
Early 1970s the air time cost was about $10/minute in today’s money. You’ll never guess why I remember that (was a teenager then).
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