Yep, that’s probably the one. Cost around $300 if I remember correctly.
Wish I knew where to get rid of it. Anchor you say? Why not!
At Hertz, we'd gotten several "early release models" for execs to use and comment on. It was truly a "stone". Heavy, cumbersome, low-power, short-duration charge, basically a long-range radio, very expensive, but would call anywhere the satellite would let it. It always drew a crowd in NYC, as no one had anything like it back then.
You can still get a retro "brick clone" of it: