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Re: CB, Good Buddy

At 09:01 AM 3/16/98 -0500, you wrote:
> I heard the CB mentioned lately.  What is the band-width of the Citizen's

The FCC legal 27MHz Citizen's Band Radio Service runs from 26.965 (ch. 1) to
27.405 (ch. 40).  The channels are spaced 10kHz apart with the exception of
a few 20kHz "gaps" or "A channels" which the FCC reserved for various other
Part 15 devices such as radio-controled model cars, early cordless phones
etc.  If you've got a decent shortwave reciever you may also hear "CB"
transmissions well beyond this range -- usually down into 25MHz and
generally stopping at 28MHz -- basically up to the borderlines of the two
nearest amateur radio bands above and below (there's also some "spillover"
into the ham bands, but most of this is forgein "skipwave" since most U.S.
CBers don't want to intentionally mess with hams, never mind the fact that
an antenna tuned for CB makes a pretty lousy 10 meter amateur antenna).
CBers achieve this extended bandwidth either with modified domestic ham/CB
transcievers or, more recently, with "export" CBs.  These are basically the
same as the FCC type-accepted models but manufactured for the non-FCC
controled overseas markets.  Such units feature multiple switch-selectable
40 channel bands above, below and including the FCC legal band.  They also
tend to have other interesting non-FCC approved features for CB such as
selectable narrow-band FM and CW (for morse code) in addition to the usual
AM and SSB modes.  I used to have one of these -- people used to think it
was pretty funky to see a CB hooked up to a telegraph key!

>I recall in the early 70s having to get the license and be actually
>concerned that the FCC was actually listening (perhaps an urban myth).  

I would tend to think so.

>Also, antenna question - we stick on the antenna
>to the van on those long trips to the midwest - is there any benefit to
>different CB antenna designs?  

Absolutely, even at 4 watts (*especially* at 4 watts)

The best moble CB antennas -- assuming they are properly mounted on the
vehicle -- are the 8' whips commonly available at Radio Schlock.  Oops I
meant Radio Shack.  Of course, these aren't the sort of things you want if
you're driving through low-bridge or heavy tree country (used to do a lot of
"pruning" myself...).  Of course any antennas shorter than this have to be
compacted with a loading coil, and cosequently are less efficent.  So
basically the closer to the 8 1/2' foot length of the "big whip" the better.
Mobile antennas should of course always be mounted as high on the vehicle as
possible, with plenty of metal below and preferable none anywhere to the
side.  The permanent metal-to-metal mounts are the best for proper grounding
and noise protection.  Magnet mounts work OK if you must have a removeable
antenna, but these can suffer from increased problems with, say, ignition
noise because they don't have a direct ground to the vehicle.

Over and out...