Dial with 'REL' LOGO
Signal Strength Meter
We are grateful to John McPherson, who added this information about the channel marks:
When the FCC was busy planning the frequency allocations after WWII to accomodate the "newfangled" invention of Philo T Farnsworth, they dedicated hunks of frequency range to "approximate uses, and assigned the "channel" numbers.
When the FM band was moved from 45Mhz to 56 Mhz, to 87Mhz to 108Mhz, there were other assignemnts too, such as channels 200 to 225 in the "new" FM band were allocated to public broadcasting, and the rest of the band was commercial, channels were of some importance.
Unless you happen to be testing for a license to become an operator of a commercial, or PBS broadcaster, you won't find too much documentation on the channel assignments any more.
Andrew R. Mitz provides a web resource with many very interesting FM-Only receivers, including an even older REL model.