Metallic paint and composite antenna signal strength

Will a metallic paint interfere with the strength of signal with impeded
antennas in a composite airplane? I have a small transponder antenna and a
Comm antenna bonded to the inside of the fuselage. Will a metallic paint
and the presence of aluminum chips screw up the strength of signal in or
out??

Thanks.

firstflight wrote:

Will a metallic paint interfere with the strength of signal with impeded
antennas in a composite airplane? I have a small transponder antenna and
a
Comm antenna bonded to the inside of the fuselage. Will a metallic paint
and the presence of aluminum chips screw up the strength of signal in or
out??

Thanks.


Yes!
This is why most radomes are marked "Do Not Paint".
Especially the transponder because the higher frequency (about 8 times
higher) wavelength is closer to the size of the chips.
John

"firstflight" wrote in message
...

Will a metallic paint interfere with the strength of signal with impeded
antennas

What is an impeded antenna?



in a composite airplane?

I ran some tests with both nav, com, dme, and transponder antennas imbedded
in the wing of a Bellanca aircraft under controlled test conditions at the
Bellanca factory back in the 1970s. The wing was wood with fabric covering.
The fabric had the standard silver (aluminum) UV dope over the fabric and
then polyurethane paint over the dope.

We measured (both ground and airborne) the signal strength from both the
standard antenna on the exterior of the aircraft and the ones imbedded in
the wings and found no degradation of signal strength from the imbedded
antennas from the reference antennas mounted on the fuselage.

Does this mean that you can't go out there and find some paint that will
screw up the reception? No. What it means is that we DID try it with one
form of metallic paint and there were no effects. Certainly you would think
that out of ten thousand internal plastic plane antennas we've sold over the
last thirty years we would have had at least ONE complaint from metallic
paint problems. We haven't. You may be the first. That's why we paint
EXPERIMENTAL on the sides of our aircraft.



I have a small transponder antenna and a
Comm antenna bonded to the inside of the fuselage.

Why on earth would you bond a transponder antenna to the inside of the
fuselage? How do you get lower hemispherical (not biconical) radiation from
something bonded to the fuselage?

Jim

What about metal flake paint?

On Fri, 24 Jun 2005 08:56:02 -0700, "RST Engineering"
wrote:


"firstflight" wrote in message
...

Will a metallic paint interfere with the strength of signal with impeded
antennas

What is an impeded antenna?



in a composite airplane?

I ran some tests with both nav, com, dme, and transponder antennas imbedded
in the wing of a Bellanca aircraft under controlled test conditions at the
Bellanca factory back in the 1970s. The wing was wood with fabric covering.
The fabric had the standard silver (aluminum) UV dope over the fabric and
then polyurethane paint over the dope.

We measured (both ground and airborne) the signal strength from both the
standard antenna on the exterior of the aircraft and the ones imbedded in
the wings and found no degradation of signal strength from the imbedded
antennas from the reference antennas mounted on the fuselage.

Does this mean that you can't go out there and find some paint that will
screw up the reception? No. What it means is that we DID try it with one
form of metallic paint and there were no effects. Certainly you would think
that out of ten thousand internal plastic plane antennas we've sold over the
last thirty years we would have had at least ONE complaint from metallic
paint problems. We haven't. You may be the first. That's why we paint
EXPERIMENTAL on the sides of our aircraft.



I have a small transponder antenna and a
Comm antenna bonded to the inside of the fuselage.

Why on earth would you bond a transponder antenna to the inside of the
fuselage? How do you get lower hemispherical (not biconical) radiation from
something bonded to the fuselage?

Jim

What about it?

Jim


"Joe Camp" wrote in message
...

What about metal flake paint?

On Sat, 25 Jun 2005 09:14:08 -0700, "RST Engineering"
wrote:

What about it?

Jim


"Joe Camp" wrote in message
.. .

What about metal flake paint?

Metal flake paint has considerably more metal, and bigger pieces of
it. Wouldn't that block the signal to and from an embedded antenna?

I have absolutely no idea. I can tell you how to run a test on it if you
would like.

Jim



Joe Camp wrote in message
...
On Sat, 25 Jun 2005 09:14:08 -0700, "RST Engineering"
wrote:

What about it?

Jim


"Joe Camp" wrote in message
. ..

What about metal flake paint?

Metal flake paint has considerably more metal, and bigger pieces of
it. Wouldn't that block the signal to and from an embedded antenna?

"RST Engineering" wrote:

I have absolutely no idea. I can tell you how to run a test on it if you
would like.

Had a customer paint his pager case with metalflake paint - didn't
work worth squat when he was done. I suspect the effect would be the
same on any radome (since that's what a pager case is).

Mark "but it was sporty lookin' " Hickey

Joe Camp wrote in message
.. .
On Sat, 25 Jun 2005 09:14:08 -0700, "RST Engineering"
wrote:

What about it?

Jim


"Joe Camp" wrote in message
...

What about metal flake paint?

Metal flake paint has considerably more metal, and bigger pieces of
it. Wouldn't that block the signal to and from an embedded antenna?

Mark ...

I mean no offense, but anecdotal evidence about painting pagers doesn't take
the place of a controlled environment test when it comes to making general
pronouncements about antennas inside of one paint or the other.

So far as I know, the paint could have leaked inside, the pager could have
crapped out from natural causes...

Jim


"Mark Hickey" wrote in message
...
"RST Engineering" wrote:

I have absolutely no idea. I can tell you how to run a test on it if you
would like.

Had a customer paint his pager case with metalflake paint - didn't
work worth squat when he was done. I suspect the effect would be the
same on any radome (since that's what a pager case is).

RST Engineering wrote:

Mark ...

I mean no offense, but anecdotal evidence about painting pagers doesn't take
the place of a controlled environment test when it comes to making general
pronouncements about antennas inside of one paint or the other.

So far as I know, the paint could have leaked inside, the pager could have
crapped out from natural causes...

They also operate in all the normal bands...
VHF Low/Hi, UHF, 800/900/1200 mhz and probably more...