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Old April 14th 12, 11:47 PM posted to uk.railway,uk.transport.london,misc.transport.rail.americas
Robert Bonomi Robert Bonomi is offline
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First recorded activity at LondonBanter: Jan 2012
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Default Telephone line numbers, prefixes, and area codes

In article ,
Roland Perry wrote:
In message , at 15:30:13 on Fri, 30 Mar
2012, Stephen Sprunk remarked:
to distinguish the technology from pre-cellular mobile telephones that
were built into automobiles and communicated with base stations with
much longer ranges than transponders on cell towers.


Are you referring to "radio telephones"?

There were cellular car phones as well, back before handheld models were
available.


My recollection is that the first cellular phones were handheld. But
they were heavy and nor very "portable". As a result it was helpful to
mount them in a car, which had other attractions like dealing with the
battery problem and making them less easy to steal. It was also the case
that the kind of demographic who was prepared to fit one in his usually
expensive motor car was very creditworthy and made lots of calls, no
expense spared.


In the U.S. the first handheld "mobile phone" was similar to the Motorola
DynaTAC 8000 (see http://utahrepro.files.wordpress.com/2011/02/first-wireless-phonemotorola-dynatac-8000x.jpg)
A friend of mine worked on the development of them in the early/mid 1970s.
The early experiential versions of the phone were *not* 'cellular', but
used regular mobile phone (IMTS) technology. Getting the required TX/RX
isolation, for full-duplex voice, in the physical 'brick' _was_ quite a
technological accomplishment.

When 'cellular' was officially introduced in the U.S, in 1983, a cellular
version of the DynaTAC was available, as well as the more conventional
'trunk mount' units. It was another 6 years before the first of the '
'modern-style' ("flip-phone", aka 'star trek communicator') handheld cellular
phones -- the Motorola MicroTAC -- was introduced.


'Bag phones' were a _standard_ automotive 'trunk mount' set, like this:
http://backofthemedic.com/wp-content/uploads/2010/06/Motorolabagbig.jpg
jut with a directly attached handset, and antenna, and a 12v (usually 'sealed
lead-acid") battery 'in the bag'.

One could fairly easily convert a bag phone to a 'fixed mobile' (automotive)
installation, or vice-versa.