[Hammarlund] Dean hq170
Roy Morgan
[email protected]
Thu, 26 Feb 2004 15:25:11 -0500
Mike Taylor wrote:
> ... What is "sweep frequency method"? Mike
Mike,
A variable, swept, oscillator produces an RF or IF test signal. The output
of the thing under test, the IF strip in this case, is displayed on the
vertical deflection of an oscilloscope and the horizontal sweep is arranged
to follow the rf generator. You get a display of the frequency
characteristic of the thing. It's very easy to then adjust the slugs or
whatever for the right shape of response.
Frills in the method include marker signals to pinpoint center or edges of
the needed bandpass, logarithmic or linear vertical response of the
detector system, and variable sweep rates to let you work on things like
crystal filters or narrow mechanical filters that ring if swept too fast.
My copy of Electric Radio magazine arrived today and has an article about a
home made sweep generator. The author is Jim Hanlon, W8KGI, [email protected]
and he built it to align his HQ-129X. I copied him on this message.
Roy
- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
7130 Panorama Drive, Derwood MD 20855
Home: 301-330-8828 Work: Voice: 301-975-3254, Fax: 301-948-6213
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