I had one of these in the mid 70's. As a six channel crystal controlled 12 volt mobile CB radio, it was a great radio. Each push button channel could be "set" with which ever separate pair of plug in transmit and receive crystals you wished. These pairs of crystals were purchased separately. Removing the screws on the case and slipping the cover off revealed two rows of six crystal sockets, One row for transmit, and one row for receive. And they could be placed in which ever order you wanted them in. late at night conversations over thirty miles was fairly common with a standard 102" whip, Or a trunk mounted base loaded whip. Pushing the power button turned it on and off. The volume and squelch controls were slider adjustments so it was simple and easy to use. And the red LED above your chosen push button channel selector let you know which channel you had selected. Sound quality was good. Disadvantages; You had to remember what channels you put in each push button's location. You could run with one channel "filled" or all of them filled, And the crystals could easily be placed in the wrong sockets. Even though they were clearly marked. The receive crystal was always 0.455 lower than the fundamental transmit crystal frequency in each "pair." of crystals.