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Old January 7th 05, 05:59 AM
Brenda Ann
 
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"young" wrote in message
om...
I live in Korea and bought my DE1103 from liypn.
My radio was manufactured by degen on 7, 17, 2004.

My local power house mediumwave stations are on 1323 and 1224 kHz.
1323kHz transmitter is located near my house.

1st weak point : 1323kHz HLKH is heard over overall shortwave
spectrum with rod antenna fully extended or wire antenna connected.
It's annoying me. This makes my 1103 useless.
My 7600gr radio doesn't show this strange phenomenon.

2nd weak point : two signals are heard on 1422 kHz with 1103's
internal ferrite bar in day time.
I think it is 3rd order product. (1323*2)-(1224)=1422.
But with my 7600gr, the ghost is barely audible on 1422 kHz.


The first two problems are most likely occuring because the radio is a
single conversion type (450~460 KHz IF only). Single conversion receivers
are easily overloaded by any strong signal, and this can cause multiple
images of the overloading station on all bands. It also will cause third
order IM like you are describing.

The third is not uncommon with any radio which uses only an injected BFO
signal instead of a true product detector.

The Degen, Kaito, and that sort are good for what they are, a bargain
basement radio capable under most conditions of receiving the powerhouse
shortwave stations. I have the little Jwin pocket radio which does fairly
well in my area. Fortunately, I live in an area where only three strong MW
signals are present, and I don't have overload problems with any of them
(603, 972, and 1440 KHz, with 972 being by far the strongest).