The earliest version of the "screwdriver" antenna as I recall were actually
manual tuned devices. I recall them being sold under the name of Bandmaster
or Super Bandmaster. Basically described as a short mast, followed by a
long coil with a sliding roller which shorted out the turns to change band.
This coil as I recall was some 2" to 3" in diameter and some 18" in length.
It was then attached to a 4 ft to 5 ft whip extending out the top. Changing
bands was a matter of sliding the rod with the roller attached up or down.
The shaft of the roller assembly was marked generally in bands to aid in
quick band changes. Today's antenna simply adds a DC motor and controller
to remotely change the tuning or bands.
A friend had one mounted on the driver side rearview mirror frame attached
to the door of his van. He operated CW with a Galaxy V as I recall. He
would change tuning or change bands while driving. Talk about "distracted
driving" Wow, that was way before the cell phone rage of today.
73
Bob, K4TAX
----- Original Message -----
From: "John" <jlockj@earthlink.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Saturday, November 23, 2013 9:44 PM
Subject: Re: [TenTec] 160 M antenna
Hi Steve,
It took me a while to find my 1993 copy of "40 + 5 Years of HF
Mobileering" - it states that the first copies of the W6AAQ (Don Johnson)
remotely tuned screwdriver antenna were constructed and used in 1974.
73,
John W0DC
----- Original Message -----
From: Steve Hunt
To: Discussion of Ten-Tec Equipment
Sent: Saturday, November 09, 2013 3:50 AM
Subject: Re: [TenTec] 160 M antenna
Rick,
That's correct!
The only published article I know of was by Tim Forrester G4WIM in
RSGB's RadCom - later included in their book "HF Antenna Collection". In
addition to the basic top-loading principle, Tim described in detail the
mechanical arrangements for the auto tuning whip: a geared motor drove a
lead screw that progressively introduced a core into the loading coil.
Tim won an RSGB award for the article - the design was in many ways a
forerunner of the "screwdriver".
73,
Steve G3TXQ
On 09/11/2013 09:13, Rick - DJ0IP / NJ0IP wrote:
> Steve,
>
> I don't understand what you are describing.
> I think you mean placing a screwdrive-tuned mobile whip on top of a
metal
> lower section.
> Correct?
>
> I have never seen or read about this.
> Do you know a source where we can read more on this?
>
> 73
> Rick, DJ0IP
>
>
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