John P. Leonard wrote:

> I've found that vendors carry RF transmitter and reciever modules using
> 433.9Mhz and 418Mhz, but nothing between; even though (here in US) that
> area is defined as "amateur."
>
> Is it possible to use the bandwidth between 418 and 433.9Mhz?  Are modules
> even available at frequencies in-between?

The reason only these frequencies are available is that 418 MHz is a
special frequency where no transmitter license is required in Britain,
and 433.92 MHz is the same thing for the rest of (most of?)  Europe.
My guess is that these transmitters are made or designed in Europe
(Radiometrix?).

Martin Nilsson                           http://www.sics.se/~mn/
Swedish Institute of Computer Science    E-mail: mn@sics.se
Box 1263, SE-164 29 Kista                Fax: +46-8-751-7230
Sweden                                   Tel: +46-8-752-1574