CMI (Chicago Musical Instruments) was GIBSON's Parent company, so AUDIO and Guitar / Music amplifier products were in their portfolio
Never heard of CMI for legitimate amateur radio HF amplifiers, for past 40 years.There were countless garage businesses made illegal CB amplifiers, tube and solid-state in 1970s -- sometimes they would use any brand name to try to look legitimate.
EASY WAY to find illegal CB amps, the more of these that are true (more likely):
1. Unknown companies or no product/serial number plate with FCC ID.
2. RF switched, since CB radios did not have external relay contacts for external amplifiers.
3. No band switching (all) or low pass filtering (solid-state amps)http://site.hfprojectsyahoo.com/low_pass_filters
4. Has very low power input, such as 5 watts.
5. Use the word: Bi-linear.
6. Bragging product or company names that reflect 1970s CB culture (Fat Boy, Texas Star, Dave Made, Bubbas Kitchen heater), or US patriotism (misdirection scam).
I assume it would work on 10 11,and 12 meters??? but what do you think about lower frequencies??
Why would you think that? Known CB amp?
Photographs would help, but if it does not have a band switch for the low-pass filter -- suspect.