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Old January 6th 04, 03:38 AM
Crazy George
 
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Harlan:

You have made two minor missteps, but they have major repercussions. They
are due to some fundamental misunderstandings of radio technology, as with
almost all beginners. Fortunately, both are simple fixes.

First, by not properly connecting the shield of the coaxial cable, it
becomes an unwanted part of the antenna, and its proximity to stuff in the
house is picking up noise. Since the house is (sort of) shielded, it is
also likely to not picking be up any useful signals. The shield of the coax
needs to be "terminated", that is, connected to the correct *something* on
both ends.

Second, the input circuits of portable radios are a compromise. They are
optimized for the whip where it is internally connected, but a different
circuit is connected to the antenna input jacks to accommodate the stronger
signals which will come from a *better* antenna. Connecting the *better*
antenna to the whip simply detunes and overloads the front end. It will
accept some higher level signal, and this occurs when approaching the whip
with these various attachments to the end of the coax, but a the ability to
accept a direct connection of a good antenna to the whip is simply not
provided for in the design.

Now, changes needed. You could make the two headed plug as Bob suggests, or
get the appropriate adapter for one of the radios so one plug will fit
either. I am at a loss to imagine what is different, unless one is 1/8" and
the other 3/32", and if so there indeed are adapters. Now, make sure the
shield of the coax is connected to the second terminal in the plug, which
will be coupled to the radio common inside the radio. If necessary to
physically install the tiny plug on the RG-59, short pieces of insulated
hook up wire can be used, just be sure to connect the shield to the sleeve
of the plug, and the center conductor to the tip.

Then, go up to the attic with another 40 feet of wire. Connect it to the
shield up there, and stretch it out as much as possible away from the
existing wire. If the attic is small, a more effective installation might
be to zig-zag both halves of the dipole so it is nearly balanced in
configuration. Don't worry about the wire being straight, the electrons
won't care.

These two changes should couple a cleaner signal into the intended high
level input of each receiver.
--
Crazy George
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