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Old January 12th 11, 06:23 AM posted to rec.radio.amateur.boatanchors
Edward Knobloch Edward Knobloch is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 113
Default Noise Bridge Hint


Hi, Gang

While researching the Heath HD-1422 noise bridge, I found
a handy DOS program by KQ6RH designed for the Palomar RX noise bridge,
which will work equally well with the Heath unit.

See:
http://www.antenna-magic.com/Rx_brdg.htm

The allowable ranges of X sub C and X sub L settings
are -70 to +70, representing the setting of the 140pF
capacitor of the Palomar. By using the input
range of to -60 to +60, the 120pF capacitor used
in the Heath HD-1422 is also accommodated by the program.

The program takes the R and X dial settings, and the freq in MHz,
and converts them to impedance in both rectangular
and polar form. The only thing lacking is a further conversion
to SWR, assuming a 50 Ohm transmission line.

73,
Ed Knobloch