This is the Midland 77-882, another example of the first generation of 40 channel radios which hit the market in Jan 1977, when the 40 channel band plan first became legal. This radio was visually identical to the 13-882c PLL 23 channels radio, which evolved from the original crystal synthesized 13-882 and '882b. The chassis of this radio was the popular Cybernet PLL-02a board which was used by a number of manufacturers including Midland, Lafayette, G.E., Hy-Gain, Kraco, J.C. Penney, Colt, and others. Feature wise, this radio included the standard offerings of Volume, Squelch (with a PA switch), "S/RF" meter, and by now the somewhat obsolete feature (stricter PLL frequency accuracies made it superfluous), of the "Delta Tune". This control shifts the receiver frequency up or down about 1 Khz to help pull in other radios which were transmitting a bit off frequency, which was a common problem with older crystal controlled radios. Also included were individual switches for the Automatic Noise limiter (ANL), the Noise Blanker (NB), and "EXT CB", a means to pipe the radio's audio out of the PA speaker (These switches were often commandeered for channel modifications). Another nice feature was the antenna warning indicator. This light would illuminate if the SWR of the antenna system rose above a preset point (Somewhere around 3:1). Rounding out the list of features, was a new 40 channel illuminated dial. Like many first generation 40 channels radios, reading the small channel numbers (Which was necessary to fit them all on the dial) was difficult, especially when mobile, which is why most of the second and later generation 40 channel radios migrated to the more familiar, and much easier to read, LED displays.
Performance was about average. The receiver was fairly sensitive and the adjacent channel rejection was about average. Transmitter power could be juiced up to about 6 watts, but modulation percentage would suffer, so it probably shouldn't be set any higher than 5 watts. The mic circuit did not employ a preamp, so consequently, a pre-amplified mic was often necessary to gain the most modulation "punch" from this radio.
But by far the best "feature", of this radio and others like it, was its Phase Locked Loop (PLL) circuit. Like most first generation 40 channel radios, the PLL was made up of generic off the shelf parts which were created for many different services and applications. This allowed a much greater number of frequencies to be selected than just the legal 40 channels. The PLL-02a chip, used in most early Cybernet chassis, was one of the best. It had a total of 511 selectable channel combinations. Naturally only a fraction of these channels were available for use, due to the bandwidth limitations of the VCO and other tuned circuits. In this AM radio form, the total range could be made to run from the low 26 Mhz range all the way up to the 10 meter band. Receiver sensitivity and transmit power would fall off as you approached the edges, but most people rarely needed that much range anyway. But after being brought up on a generation of the limited capability of modified crystal radios , and the often unstable operation of VFO's, this "new" method of PLL frequency generation was almost euphoric by comparison, and it was very tempting to "push the limit" just to see how far you could go, even if you'd never use all the extra frequencies.
I owned one of these radios in the early to mid 80's. I purchased it from Uncle Albert for a good price, when he bought his Johnson 4740 SSB radio. Needless to say, I experimented and modified the heck out of the radio. Frequency mods, a switchable modulation limiter, and a switchable attenuator to reduce strong signals, pretty much rounded out the list of my mods. I used this radio as my primary mobile rig in my truck until 1984, when I sold it at a hamfest in order to buy one of the "newfangled" "Export" radios, a President Jackson. One a scale of 1 to 10, I'd rate it at a 5. It was not a super great performer, but what it lacked in performance, it made up for in capability.