[BC] Older Cordless phones

[Dana Puopolo]

Actually, the channels at 1700 kHz were illegal. The FCC banned the sale of
those phones, but by then they were so popular it took years for them to
disappear from that band. Those cordless phones also used CB channels at 27
mHz. Since they used FM, they were also illegal there. The 49 mHz frequencies
were put tere by the FCC back in the mid '70's for 100 mw walkie talkies to
get them off of 27 mHz. 46 mHz was added for use by cordless phones in the
'80's.

-D



------ Original Message ------
Received: Thu, 13 Jul 2006 05:58:34 PM EDT
From: Kevin Tekel <amstereoexp at yahoo.com>
To: broadcast at radiolists.net
Subject: [BC] Older Cordless phones

Paul Walker wrote:
> I know there used to be some older cordless phones that operated just
> above the AM Expanded band as it sits today... Do any of them still
> exsist somewhere today?

Info on this is sketchy but it seems that the earliest allocation for
cordless telephones was 6 AM channels at 1.7 MHz, although I've also heard
that 1.7 MHz phones were much more popular in Europe, and these used NBFM
(narrow band FM).  Anyway, in 1980 the FCC allocated 10 FM channels for
cordless phones at 27 MHz, but it seems that the allowed power level was
rather high, causing crosstalk problems and inadvertent three-way
connections when two neighbors were both using 27 MHz cordless phones.

So in 1986, the FCC allocated 10 FM channels at 46 and 49 MHz (I think
46 MHz is for the base and 49 MHz is for the handset, but I could be
backwards on that).  This was later expanded to 25 channels, in various
groups between 43 and 50 MHz.  Then in 1990 came the 900 MHz allocation
for cordless phones, 2.4 GHz in 1998, and 5.8 GHz in 2003.  I'm personally
a bit confused that the alleged advantage of these higher frequencies is
"increased range" -- isn't 5.8 GHz getting up to the point where the walls
inside a house will block the signal?

If you really want a vintage cordless phone (either 1.7 or 27 MHz), look
out for one where the handset looks like a walkie-talkie and has no
keypad.
On these old phones the handset was cordless but if you wanted to dial a
number you had to walk up to the base.


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