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Subject:
From:
colin McDonald <[log in to unmask]>
Reply To:
For blind ham radio operators <[log in to unmask]>
Date:
Thu, 28 Oct 2010 15:45:01 -0600
Content-Type:
text/plain
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text/plain (86 lines)
I was looking up the FRS/GMRS and shared frequencies the other day to add to 
my list of frequencies that i'm rebuilding after losing everything on my 
laptop a while back.
I came across a website that listed similar services around the world.
There are some pretty interesting frequency alocations especially in asia. 
Tailand uses frequencies in the 300MHZ range for their CB service, offering 
99 channels.
I can't remember the URL or I would post it.
If you do a google search on FRS, you should come across the same website I 
did.
I seem to remember one country also having a CB service in the 220MHZ range 
or close too it.

73
Colin, V A6BKX
----- Original Message ----- 
From: "Martin McCormick" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, October 28, 2010 9:40 AM
Subject: Re: The bands


> I've been kind of busy with work so sorry for the late reply.
> Chip Johnson writes:
>>     In the US, as I recall, it's 150 miles. I used to operate on 11
>> meters and always wondered why, if we weren't supposed to talk over 150
>> miles, we were allocated a group of frequencies where it was quite easy
>> to do so a good deal of the time. Guess that's government for ya.
>
> Well, not really. It's technology and government's attempts to
> make the best of a not so good situation.
>
> CB in the United States started in 1958 after about ten
> years of planning. Keep in mind that about ten years means 1948.
>
> The idea was to have a low-cost low-power radio service
> for private citizens to use for personal communications or small
> business applications. Oh yes and it would be nice if they
> actually worked.
>
> What became the CB frequencies was about the highest
> frequency one could build consumer radio gear that would
> transmit and receive efficiently enough to barely qualify as
> useful.
>
> There was an article in "Popular Electronics" around
> 1965 or so that described the history of CB in the United States
> and it may have included the words "Big Brash Band," but I may
> also be mistaken.
>
> There were some pilot projects across the US in the
> early to mid fifties but 26.965 to 27.something was still the
> Eleven-meter ham band for most people. It also had something
> else on it that made it undesirable for hams. It had ISM or
> Industrial Scientific and Medical frequencies in it. Those are
> usually heaters for drying lumber or other industrial heating
> applications plus medical diathermy gear such as what your
> doctor might connect to a sore muscle in your back or leg. These
> were bad-boy transmitters that had no filtered power supplies
> and either ran straight AC on the plates of their tubes or used
> a half-wave rectifier so what you heard was a drifty loud buzz
> at 60 HZ in North America or 50 HZ from some parts of South
> America and most of the rest of the world.
>
> Eleven meters was a waste land full of a few hams and
> lots of diathermy which is why we lost it as a ham band.
>
> An old-timer told me that there were a different class
> of CB channels in the UHF range around 450 MHZ and they were
> absolutely useless. No output power and regenerative receivers.
>
> My own personal opinion is that eleven-meter CB should
> go away and the band returned to amateur use all over the world.
> We can make use of the skip and do so legally. Commercial uses
> of those frequencies would be hampered by the variable
> propagation characteristics.
>
> The FRS radios in the 462 and 467 MHZ ranges are exactly
> the kind of low-cost communications that were envisioned in the
> forties and the lack of skip means much more consistent
> operation.
>
> Martin McCormick WB5AGZ  Stillwater, OK
> Systems Engineer
> OSU Information Technology Department Telecommunications Services Group 

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