In message , Irv Finkleman
writes
"M. J. Powell" wrote:
In message , Irv Finkleman
writes
RB wrote:
Brings back scenes from old WWII movies....
Small loops are still used and seem to be very effective for DF. I
think that
the ARRL antenna book provides information in this direction. One system I
saw used a short ferrite dipole array.
In most cases, DF sets displayed their goniometer outputs on a CRT or as
signal strength on a meter. In this case, the dots and dashes melded into
a continous output because of the persistence of the CRT or the AGC delay
of the receiver.
I don't think there was a swinging goniometer with the CRT DF set. The
output of the two loop aerials fed the X and Y plates respectively so
that the trace appeared at the right angle and the bearing was read from
the screen.
Mike
There were a number of different types of DF sets. Some, as you
point out had x and y
plates connected to the loops, another had a mechanically rotating gonio.
We had one for radar detection which used horns with crystal detectors in
it which went to x and y plates (through amps).
That's interesting. I didn't know of microwave DFing.
The HFDF used loops feeding
a mechanically rotating gonio with output to a crt.
Ah! Right. Now I've got it. Thanks.
Mike
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