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Old July 19th 07, 05:27 PM posted to sci.electronics.basics,rec.radio.shortwave,rec.radio.amateur.antenna,alt.cellular.cingular,alt.internet.wireless
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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First recorded activity by RadioBanter: Jun 2007
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Default A more rational approach -- how I would like to change the cell phone industry.

DTC hath wroth:

Radium wrote:
On Jul 1, 7:24 am, wrote in
http://groups.google.com/group/sci.e...0c8ed13?hl=en&
how would u like to change the cell phone industry?


Analog cell phones should stop using FM and should start using AM at
whatever practical radio frequencies available.


That idea was touted and attempted over twenty years ago. Back when
cellphone handsets were better described as concrete blocks instead of bricks.

Gosh...I miss my 70 watt Micors and darn near crystal clear audio on IMTS
systems with 30 mile range. But that was thirty years ago.


Who said they were gone? Fire up your scanner or service monitor on
the old IMTS frequencies and you'll hear the idle tones or sometimes
idle chatter.
http://en.wikipedia.org/wiki/IMTS_Frequencies
There's still some IMTS phone systems running in "rural" areas.
http://en.wikipedia.org/wiki/Improved_Mobile_Telephone_Service
Brings back fond memories of the "RCC wars" (radio common carrier).

However, you're right. I really miss my Motorola T1234 mobile
telephone and giant Secode control head. It really impressed the
various ladyfriends in college.
http://www.privateline.com/PCS/mobilephonepictures.htm
Too bad (for Mr Radium) it was FM.

I did work on an AM/SSB mobile telephone system in about 1974. I
never saw it but as I vaguely recall, it operated on various HF
frequencies in some part of Africa. Operation was similar to operator
assisted MTS (mobile telephone service) but on HF. It was basically a
phone patch hung on an HF base station. We were trying to add
signaling so that users would not have to listen to the channel noise
all day in order to receive a phone call. Our scheme sorta worked on
SSB, but the tones drove those that didn't have muted receivers nuts,
so it was eventually abandoned. I think the system was up until about
1990, when something blew up and the operator couldn't find parts or
something.

Of course, there's always the HF marine radio telephone service, which
still operates on various HF frequencies with real live human
operators. They're all currently using SSB, although that wasn't
always the case. In the 1960's and 70's, almost everyone was using
AM.

I got a great name for Mr Radius's system. Reactionary Radio.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558