Who say's Ham radio is DEAD ? The fiddling ,building, Experimenting IMO is a
big part of Amateur Radio. In today's throw away society , it's a bigger
challenge to explore or tweak a unit or a system That's why antennas are so
intriguing , because no two installs are exactly the same. You sound like me
Ron..." I found an old Broken car power antenna" HAHAAHAH I think I my have
one laying in my,, you never know my need that pile !!! 73's Wayne W3EA
> Date: Thu, 15 Dec 2011 05:23:41 -0800
> From: ron.e.spencer@gmail.com
> To: topband@contesting.com
> Subject: Topband: motorized matching caps
>
> I recently increased the height of the tower I shunt feed for 160 to
> 105'. Presently no antennas on the top only a bit of mast out the top.
> The 2:1 BW is quite narrow so I decided to try to motorize one of the
> caps in the omega match. First I used large air variables to get a
> match. Then measured and found I had a vacuum variable that could be
> used which was great because they take more "rotation" of the shaft to
> change capacitance vs the air variables.
>
> I was trying to decide what motor to use and was digging around "stuff"
> I had. I found an old broken car power antenna. Opening it I found it
> had a quite large motor, 12V of course. I used the large "wheel" that
> the plastic cable to raise and lower the mast was wound on to adapt to
> the capacitor. Using the large wheel gave me a slower rotation which
> turned out to be the perfect speed. Its fast but again, with the vacuum
> variable it takes more movement so it all turned out well. And, best
> part, the motor and gearing was FREE!
>
> 73
> Ron N4XD
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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