Telamon wrote:


The 7030 has a metal case and so is shielded. This looks like a good
case of the BCB station coming in on the power cord through the house
wiring. With the 50 ohm resistor on the antenna terminal use a RF choke
on the DC power cord to the radio to see if the AM station goes away.
Same should work for any other radio that has a metal case.

The non-shielded radios may have the RF go through the case as an
additional path to consider.

--
Telamon
Ventura, California
--------------------------------------------
I can only wish I had my own 2030+. This was a borrowed unit
from a friend who was wrapping up the sale of her family farm
after graduation. I did try to place several ferrite RFI "snap on",
and while I could reduce the interference, even with over 10
on the power cord I still had a very weak signal on 770 and the
770+590.

I was really suprised by the R390 and R392. In these receivers
the RF was getting in through the audio line. High level RF is hard
to completly supress. At least the 770 station cleaned up their
harmonics. A nice letter with the comment that I would hate for them
to get fined for improper operation got the problem solved within
a week. The 1540, 2310 and 3850 were very strong.
No 4rth harmonic at all.

A high pass filter ruled out my receivers.

I wonder how many people have MW ingress and don't know it.
Sometime "real soon" I am going to psot the results of my RF
week end and how bad normal single or double brain only coax
is. By bad, I mean allows LW/MW and HF if any stations are
close or strong enough to leak in even with out an antenna connected.
I tested 100' of various good quality (Belden) coax. and one run of
200' (borrowed) run of triax.

Terry

Terry