Antenna Recommendation
On Sat, 21 Apr 2007 11:04:01 -0400, "Robert A. Turpin"
wrote in
:
I would say the roof. You can put a shorty on there while commuting to
work, and keep a firestick or ss whip behind the seat when you hit the
highway or find a nice hill.
If I'm going with the roof, what's to gain with a permanent mount vs. a
Wilson magnet mount?
Versatility. You can put any standard 3/8-24 threaded whip on there,
whether it's super short or the big 9' whip. All you need is a 25 cent
wrench in the glove compartment to get them on or off. It's also
cheaper in the long run since mag mounts often get stolen, and whips
are both cheap and plentiful (especially at garage sales). And no
mag-mount will outperform a 9' whip -- period.
The reason for mounting it on the roof is to get the bottom of the
antenna (the part that radiates the most) above all the metal of the
vehicle. Mounting the whip to the bumper or trailer hitch and your
rear clip will absorb and/or scatter part of your signal, and will
affect reception by the same amount.
I see from your other post that you aren't familiar with amps. Just so
you know, CB amps are illegal. If you get caught the FCC will either
send you a letter telling you to stop, or ask to inspect your station
to confiscate your amp. If you ignore the letter, or refuse to let
them take your amp, you will get slapped with a fine of several
thousand dollars (yes, -thousand-). If you're ok with that, here's the
dope on amps:
Your standard 40-channel CB puts out 4 watts of RF. In order to double
your range you need to quadruple your power. But as you increase your
range you will step on other CBers in the area you are covering, so
you need to use the amp with respect to other CBers. At some power
level you will no longer get any more range (law of diminishing
returns) which usually happens around 100 watts or so, depending on
your terrain. Any more power and you are basically in an RF drag race
with big dummies with big amps to see who can stomp on everyone else's
signal.
If you DX then you may find that power doesn't matter much, skip is
either there or it isn't, regardless of how much power you use. In
fact, at least one person on this group has DXed half the planet
without an amp at all.
If you haven't purchased your amp yet, be warned: most of them are
junk. They may claim that they are "linear" but are not, and will put
harmonics all over the spectrum, including the neighbor's television.
A low-pass filter will help but not completely. Just like everything
else, you get what you pay for.
Also, if an amp is rated for 100 watts, don't expect to get more than
25 watts carrier (dead-key). The reason is that most amps are rated
for 'peak' power which is fine if you are running SSB, but the
majority of CB is done with AM. In that mode, peak power is four times
the carrier, so you must reduce the amp's input until the carrier is
one fourth of the rating of the amp.
Hope that helps.
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