>Have been reading your comments on GlaStarNet with interest. I have a
couple
>of questions that perhaps you could help me with.
>
>1. I purchased and ACK ELT for installation in the GlaStar. In the
>installation instructions, it states that the antenna should be installed a
>minimum of 5 ft. from any com antenna.
>
>It does not state why, nor does it state the consequences if the above
>"should" is violated. The only two things I can think of is that if the ELT
>were activated, it could overload the rf into the com receiver.
>Alternatively, is it possible the com signal could overload the ELT
>transmitter, active or inactive? Do you have any knowledge of why the
>instruction is included?
Like software designers who believe their work is the most important
program on your computer and loads up your quick start icons with
a half dozen links to THEIR program, hardware designers constantly
dream about the ideal install of their equipment in your computer -OR-
airplane.
In the real world, there are few performance issues with respect to
antennas that ever get idealized on airplanes . . . especially the
lower frequency devices (VHF) . . . gee, when I got started in
electronics, 100 MHz was the edge of no-man's land . . . guys who
could make things work at 2-meters (144 MHz) were revered for
their technical accumen that was rumored to include special
blessings and perhaps a bit of black-magic.
Nowadays, we're all wishing that 50 year old VHF "junk"
would just go away. Transponders, GPS and Cell-phone
antennas (900 MHz and up) are about as close to ideal installs as
you can get in any vehicle. 100 MHz has become the new "low"
frequency service with its huge, bulky antenna and quirky idealized
requirments that are hard to achieve on anything smaller than
a DC-9 . . .
If your ELT were really, Really, REALLY close to the com
transmit antenna, there might be some risk of the com transmitter
popping somethign in the ELT but were talking inches of separation.
Given that the output stages of the ELT are another TRANSMITTER
designed to handle considerable power comparted to the sensitive
amplifiers in the front end of a RECEIVER, it's unlikely that
the ELT can be damaged by proximity coupled energy from another
light plane transmitter (airlines use 25 watt transmitters and
are potentially more dangerous to other on-board systems).
Bottom line is install things were they (1) fit, (2) look best
or (3) work best . . . according to most builders choices
(1) and (2) are handily accomodated by installing
all antennas inside the tailcone . . . keeps of the bugs, rain,
and make the airplane look really sharp. Given that you've probably
spent $K$ on your electro-goodies, it would be nice that they
also work . . . My best advice is to look over installations
other builders have been flying and if they're happy with the
way things work, your chances of a similar result are good.
>2. I am thinking (and dealing with time conflict) of attending your seminar
>in Portland (possibly another preson as well). What is the sign-up
deadline?
> Can we sign-up/pay at the seminar?
The Portland gig was postponed for lack of interest. We're in the
re-organization mode. Watch the seminar webpage. We'll also announce
new dates and places on the various lists.
To other list-servers . . . I've been out of town a lot over the
past month and have a couple of trips (weekend only) yet this
month . . . this is why I've been so quiet lately on the lists.
I've been able to teach my laptop how to dial using a calling card
so I was able to keep up with most e-mail while Dee and I were on
an extended trip earlier last month.
Right now, I'm sitting at a folding table in our new office
here at the house. No furniture in it yet but I do have the
copy machine installed. Spent most of the weekend installing all
the telephone and networking cables in the walls . . . carpenter
things are not my favorite pastimes! Got all the phone system
up and running about 1 a.m. this morning.
When all the office furniture is out of the shop, we'll be adding
about 200 square feet of new shelving and plan to greatly expand
our electro-goodies inventory. I've got a guy working on a new
website with a shopping cart catalog. The goal by the end of the
year is to become a truely one-stop-shopping source for all your
electrical system needs.
It's going to take several more days to get the office back together
so I may continue to be more "distant" than usual . . . but I'll
be back!
Bob . . .
////
(o o)
< Independence Kansas: the >
< Jurassic Park of aviation. >
< Your source for brand new >
< 40 year old airplanes. >
http://www.aeroelectric.com
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