Look at the way Hi Sierra builds their newest model screwdrivers. They use
a coil -- 1/2 in dia -- abt 14 turns
-- 1.5 uH is my guess.
Looks like the coil is way to go rather than the toriod matching
transformer.
Any comments?
K6EXO
----- Original Message -----
From: Dave Jordan <wa3gin@erols.com>
To: Towertalk <towertalk@contesting.com>
Sent: Sunday, July 04, 1999 4:34 PM
Subject: [TowerTalk] Matching the BB3
>
> Hi Folks,
>
> Now that it's warm enough outside (103 degrees) I thought I'd spend the
> afternoon on the concrete
> driveway and fool around with matching the input to the BB3 mobile
> antenna. Found some scape
> 2.5 inch airdux, cut off a 14 turn hunk. Connected one end of the coil
> to the antenna input and the other to ground. Tapped the coil with the
> center conductor from the coax...couldn't get a good match. Moved the
> ground sideup the coil with a ground jumper. Ended up with using four
> turns of coil with the coax tap at the feed point of the BB3 and the
> ground strap located 4 turn below. I set the antenna to resonate at
> 7.225mhz before I started this exercise.
>
> The measurement/results were are follows:
>
> Frequency R X SWR
> 7.185 100 21 2.0
> 7.210 69 0 1.3
> 7.232 53 0 1.0
> 7.251 43 10 1.2
> 7.265 39 18 1.6
> 7.281 34 25 2.0
>
> SO, does it look about right?
>
> HAVE FUN,
> dave
> WA3GIN
>
>
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>
>
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