Back in the '80s, early 90s I was a Police Officer. We used scanners for interoperability between departments. My PD used VHF, the neighboring PD used UHF, and the State used HF. I would talk on my freq and get a response over the scanner from the other PD. It worked surprisingly well. All cruisers had 8 channel scanners with crystals, I don't recall the model.
Been monitoring for about 35 years.
73, K8HIT
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