"Zoltar" wrote:
I am acquiring a Sony icf-7600gr and want to put up a longwire aerial for
it- can some one advise on the specs viz wire length etc. also is it
necessary to run a coxial cable from the aerial to the radio and if so how
does one attach (both ends) ie is the shielding attached to the aerial as
wellas the centre core

Does the 7600 have a jack for an external antenna, and if so, what does it
look like?

You don't really have to use coaxial cable. In fact, a random wire (it's not
really a longwire) will not be a good match for coaxial cable unless a
matching transformer is used.

You can run a wire of any random length (25 to 50 feet) from the radio to
any convenient support (tree, pole, etc.) Keep it away from power lines, but
try to get it up high and away from sources of interference such as TVs and
computers. It can be run entirely indoors, but that will probably pick up
more noise and interference.

You may find that a longish wire will pick up so much signal that it will
overload your radio. That won't damage the radio, but will generate intermod
which will adversely affect reception.

If you don't have an external antenna jack, just clip the end of your wire
antenna to the telescoping whip. If signals are too strong, just wrap a
couple of turns of the (insulated) wire around the whip.

The antenna wire can be any convenient gauge that's strong enough
mechanically. It should be insulated anywhere it touches anything.

Some folks use a 9:1 matching transformer with their random wire. When
properly grounded, that type of system can reduce noise pickup. What matters
in shortwave radio reception is not so much signal strength, but signal to
noise ratio!

Art Harris N2AH