Hey Casey and the gang;

WOW !! You got an Extra Class license for your first license... and it is so
brand spanking new (yesterday) that your not in the usual databases, but
rather just in the FCC database. I am impressed. (Most guys get a Tech.
license to fly radios.....)

Um, yeah..... even in bigger rockets the antenna seems to end up sticking
out of the forward e-bay bulkheads just as Keith mentions. I make my
antennas out of miniature hardline sma jumpers and they end up similar to
what you described Casey in that they **only** have the connector,
dielectric, and inner conductor remaining. (They are a 1/4 wave long with
the conductor at one end and nothing is connected to the "shield", as I do
NOT extend the antenna with a coax 'jumper'.)  The Teflon dielectric makes
the antenna stiff and I simply use some electrical tape stretched over what
sticks out of the bay. The tape also seals the hole so gases should not
penetrate into the 'sanctum' of the e-bay.

One thing to be sure to not do is to fold the antenna back along itself OR
the feedline, (if you are going to use feedline to extend it) OR the
telemetrum itself. The antenna really needs to be 'free and clear' of
conductive obstructions.

Oh yeah, in some testing I did last year, I found it prudent to make sure
that your battery is out of the way of the antenna AND not too close to the
telemetrum as well, more especially if you try to simply place the
telemetrum on top of the battery. There needs to be some spacing between
them, not much, but a small amount to ensure good operation.

Hope this helps some and congrats on getting your license OM.....es vy 73
de;

- Bob
w9ya

P.S.... I think you might have figured this out by now, but the antenna is
the MOST important part of any 'rig', which makes for much enjoyment when
you see guys spend ALL of their time and effort on the radios and then spend
NO time on the antenna. And yes, ham radio operators are notorious in how
little they know about antennas, yet it is truly the heart of any
communications stations they employ.....As you point out, there is precious
little about them on the exams.

On Fri, Feb 25, 2011 at 1:14 AM, Keith Packard <[email protected]> wrote:

> On Thu, 24 Feb 2011 23:48:23 -0800, Casey Barker <[email protected]>
> wrote:
>
> > I'm planning to put a Telemetrum in the fiberglass avionics bay of a
> > Performance Rocketry Little Dog Dual Deploy, but the bay is only 7" long,
> > which poses a packing issue with regards to fully extending the
> Telemetrum's
> > ~7" UHF wire antenna.
>
> In my LDDD, I drilled a 1/4" hole in the forward bulkhead and glued a
> piece of acrylic tubing, then slid the existing wire antenna up inside
> that. The tubing is slanted so that it hits the wall of the forward tube
> to try and keep it mostly out of the way. I pack the antenna and shock
> cord around it while sliding it into the airframe so that things don't
> get mashed in weird ways.
>
> Works great!
>
> --
> [email protected]
>
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>
>
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