On Tue, 30 Aug 2005 20:12:00 -0400, "asdf"
wrote:

thank you for this amazing post. I just have one question;
You say that i can use telescopic antenna as well as loop antenna
simulatenously with my radio. The manual for my Sony 7600GR
however says that when i use external antenna (loop antenna)
that my telescopic is supposed to be retracted. Any reason you
can think why would that be.


No one's replied so if I may: The 7600GR AM and SW RF amplifiers
are simply connected in parallel, with no on-off switching, to the
mixer. The high 55MHz 1st IF gives very good AM broadcast band
image rejection in SW but is less effective conversely. The whip
also (as pointed out here) picks up noise and that addition may
contrubute to overloading the mixer and AGC circuit which now
(with a an external antenna) has very high input.