Mystery Module on Rear Glass

[Paul Workman]

Originally Posted by 32valvesftw

I had one similar to that as well, it used a 12V lead acid battery, I think.

Yup! A 12V gel cel, actually. bought mine when I lived in Atlanta and it worked pretty well, long as I was near a city. Even worked out on the South Dakota prairie while eradicating prairie dogs (one at a time) for a rancher friend.

The industry was just getting started then. The frequencies were lower than now (may have been analog too, IIRC) and the power was higher, but so it had to be b/c cell towers were much farther apart than now.

As the industry expanded and the number of cell towers continued to expand - more for some companies than others (Verizon "Can you hear me now?" especially), the format changed to CDMA (both digital & secure) in the USA, frequencies got much higher so antenna size shrunk accordingly, and "flip phones" became the rage for a time. (And, GM experimented with DOHC V8s for a time b4 reverting back to pushrods until recently (like going back to analog BAG PHONES...but I digress!).