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Old March 30th 05, 07:08 PM
Smith-Gaspard W4ONO
 
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Hello Steve, et al ...

I am not familiar with your shortwave receiver, but perhaps you can tell
me the
receiver controls on the front.

Most communications receivers will have certain circuit designs that
will prevent
"overload", such as an automatic gain control [AGC] which automatically
attenuates large amounts of radio frequency [RF] energy entering the
first stage
of your tuned circuits. If your receiver does have an AGC switch, try
turning this
circuit in the on position and see if there is any difference.

Good communications receivers will have one to two stages of RF
amplification
circuits which are designed for selectivity. These circuits are
manually controlled
by a control on the front of the receiver called an RF control. By
decreasing the
RF control you will decrease the amount of RF amplification and bring
back the
selectivity to the front-end stages. Look in your instruction manual
and see what
your Intermod-Distortion [IMD] specifications are. This is the ability
of your
tuned circuits to reject received signals from heterodyning with the
local oscillator
[LO] during the mixing stage.

After you have read your manual and are satisfied with the ability to
control your
receiver correctly, I will be happy to suggest various external
wide-band antennas
that are simple to construct.

73 de Jim W4ONO .-.-.
West Central Gulf Coast of Florida, U.S.A.

Steve wrote:

Yes, Im receiving lots of signals but not music or speaking just a loud
rumbling like the sound of an aircrafts engine

steve