KB7AIL wrote:
Anyone here have experience with 'old school' mobile telephone service?
I suppose that depends on how old is "old". Early mobile service was low band with the base transmitting on 35mhz and the mobiles on 43mhz.
There were a total of 8 channel pairs. It seemed channel "ZO" was the default for most urban areas. In Seattle PNB was on ZO and Whidbey Tel was on ZY out of Langley.
This was a manual service using a mic or PTT handset.
Next there was MTS on 152/158mhz which was an 11 channel full duplex capable system. These channels were the "J" and "Y" series and assigned to telcos. There was also a set of 14 VHF RCC channel pairs.
In the not too distant future Secode encoder/decoders made it possible to have direct dial service (IMTS). I remember equipment from Glenayre, GE, and Motorola. At one time I had a GE rotary unit and a Motorola Pulsar II pushbutton unit.
Canada had a similar system called Autotel on the 152/158mhz pairs.
Next came UHF channel pairs on 454/459 mhz. Telco had 12 channels ("Q" series") using the same Secode system as VHF and RCC had 14 channels.
On adjacent UHF frequencies (454.675-454.975) is the airphone system which is still active in some areas. You can tell the airphone system by a constant DTMF idle tone.
I still have some coverage maps from the Pacific Northwest.
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