Today's Message Index:
----------------------
1. 03:48 AM - Re: Re: Ammeter, voltmeter and other diagnostics (BobsV35B@aol.com)
2. 08:53 AM - Re: Re: Ammeter, voltmeter and other diagnostics (Robert L. Nuckolls, III)
3. 08:54 AM - Re: PolyFiber silver coats and their effect on radio signals (Robert L. Nuckolls, III)
4. 09:10 AM - Re: PolyFiber silver coats and their effect on radio signals (Mike Welch)
5. 09:52 AM - Re: PolyFiber silver coats and their effect on radio signals (Robert L. Nuckolls, III)
6. 10:00 AM - High Definition MotorSports camera for your aircraft (planecrazy1)
7. 10:57 AM - Re: PolyFiber silver coats and their effect on radio signals (Bill Boyd)
8. 11:26 AM - Re: PolyFiber silver coats and their effect on radio signals (Dennis Golden)
9. 11:36 AM - Re: PolyFiber silver coats and their effect on radio signals (Robert L. Nuckolls, III)
10. 06:23 PM - Com antenna (N81JG@aol.com)
11. 08:34 PM - Voltage regulator/dropper (Phil)
12. 08:38 PM - voltage regulator level change? (Phil)
13. 08:44 PM - Re: Com antenna (Robert L. Nuckolls, III)
14. 10:00 PM - Re: Com antenna (N81JG@aol.com)
Message 1
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| Subject: | Re: Ammeter, voltmeter and other diagnostics |
Good Morning Stan,
Here I am a couple of days late getting to my mail, but I would like to
comment. Just one low time pilot to another low time pilot. <G>
I like having the data for my personal perusal. My reasoning is about the
same as yours. Thanks for the posting.
Happy Skies,
Old Bob
Do Not Archive
In a message dated 6/4/2010 12:34:34 P.M. Central Daylight Time,
Speedy11@aol.com writes:
James,
Design your electrical system to make you comfortable. If you are happy
with Z-11, then use it.
Realize that you can monitor amps and volts and still rely on your plan B.
Personally, (17k hours in mil, airline, GA (owned 9-built 1), 98% of time
in VMC) I prefer having information in my cockpit. I cannot make decisions
without information. Any plan B, whether electric-related or not, cannot
make decisions for me. As PIC, I have to make decisions - and I need
information to make decisions.
In my RV-8A, I display and monitor amps at two locations and voltage on
the main and standby busses. I guess I'm a control freak, but when it comes
to being PIC, that could be a good thing.
Bob N has bucket loads of electrical knowledge and my hat is off to him
for sharing with and educating ignorant people like myself. But, when it
comes to operating an airplane, I differ with his opinion. I prefer to have
more, not less, information in my cockpit.
What one does with that information is another story - and that is where
Bob's concept comes into play. He indicates that pilots should not use
information about their electrical system to make assessments or decisions
while airborne. Bob advocates having an electrical plan B that removes the PIC
from the airborne decision process. As you clearly explained, the intent
is to make electrical problems idiot-proof. Nothing wrong with that as it
can make aviation safer and simpler.
But, the pilot in me wants information. For me, more information is
better.
You can build Z-11 and still display electrical information in the
cockpit. The displayed electrical information may do nothing more than confirm
what the flashing LV/OV light is telling you.
Build it how you like it.
Regards,
Stan Sutterfield
_www.rv-8a.net_ (http://www.rv-8a.net/)
do not archive
Is this approach a good one? It makes sense to me, a
daytime-VFR-for-the-foreseeable-future pilot, not to be trying to
fathom electrical problems in-flight. Am I missing something though?
Any thoughts you might have on the subject would be greatly
appreciated.
(http://www.matronics.com/Navigator?AeroElectric-List)
(http://www.matronics.com/contribution)
Message 2
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| Subject: | Re: Ammeter, voltmeter and other diagnostics |
Bob N has bucket loads of electrical knowledge and my hat is off to
him for sharing with and educating ignorant people like myself. But,
when it comes to operating an airplane, I differ with his opinion. I
prefer to have more, not less, information in my cockpit.
What one does with that information is another story - and that is
where Bob's concept comes into play. He indicates that pilots should
not use information about their electrical system to make assessments
or decisions while airborne.
No. Not DEPEND on information while airborne . . .
Bob advocates having an electrical plan B that removes the PIC from
the airborne decision process.
No. The effective Plan-B MUST be crafted and understood by
that same PIC. The PIC is very much in the loop. The task
is to do all the investigation, deduction, design and
planning ON THE GROUND. The cockpit is a lousy classroom
for crisis management.
By the way, these are not ideas unique to me. They have
been handed down by generations of thoughtful
students/teachers of the art and science of elegant
systems design. What I've offered is not mere opinion
but fact demonstrated by our ancestors.
As you clearly explained, the intent is to make electrical problems
idiot-proof. Nothing wrong with that as it can make aviation safer
and simpler.
I think you have mis-interpreted my offerings.
"Idiot proof" was never a design goal.
When one crafts a complex system wherein the
smallest of failures represents a major operational
problem (like a speck of rust clogging your carburetor
jet) the prudent designer strives for failure tolerance.
I have produced an analysis of the accident that
totaled an expensive airplane, injured some folks
and now plagues the lives of individuals who would
MUCH rather be flying, water skiing, or reading
a good book. All this expense, inconvenience,
pain and taxation of $time$ came about because
some individuals didn't know what they didn't know.
They stacked extra goodies together with some
notion of adding "safety" while in fact, crafting
a system guaranteed to fail. Poor application of
a $3 worth of components set the stage for $millions$
of misery. This pilot had perhaps 30 seconds to do all
the multi-tasking that was demanded of him before
the inevitable came to pass.
Adequate and accurate information about system operation
and behavior in both normal and failure modes is necessary
for REDUCING probability of failure, REDUCING the effects
of any given failure and crafting a PLAN-B for comfortable
management of said failure.
But, the pilot in me wants information. For me, more information is better
Absolutely . . . but a desire for lots of lights and
dials in the cockpit and plans to sift offered
data in flight suggests a lack of confidence
in understanding the system.
The goal was never to make any part of the
system idiot proof . . . it was to gather together
EVERY simple-idea about system functionality. No
data point left unexplored. I.e., everything
to be known was known and ALL information was
considered . . . BEFORE THE AIRPLANE EVER LEAVES
THE GROUND.
It was my suggestion from the beginning that one
can craft a system with a very low parts count,
low cost of ownership and PRE-PLANNED steps for
failure contingencies. This is NOT a task for an
of, by or for the idiot. Artful implementation of
these design goals yields the simplest of systems
to operate thus reducing risks to the operator's
ability to multitask: to aviate, navigate, communicate,
diagnose, mitigate failure, and perhaps pray while
the wheels are off the ground.
Like my teachers before me, I encourage everyone to KNOW as
much about the aircraft's function as they are capable and
willing to acquire. I encourage everyone to understand
how ALL the simple-ideas combine to form a useful,
comfortable, inexpensive recipe for success.
Consider the notion of stacking of lots of dials and
gages on the panel with a plan for using them in flight to
become better educated about what's wrong and
what to do about it. Does this not suggest that the designer
doesn't know what he doesn't know but plans to learn
it later . . . literally "on the fly".
The system with a single LOW VOLTS warning light
was never a design goal for idiots . . . it was
but one component in a system crafted with a
design goal of failure tolerance and comfortable
operation by the most knowledgeable of builder/
operators. Indeed, the artfully crafted design
goes far beyond data displays.
It is best that lots of cockpit data be used for
operational enlightenment and/or in-flight
entertainment than for DISCOVERY OF NEW WAYS to
deal with an unfolding crisis.
An interesting study in failure modes effects
analysis:
Consider Figure Z-13/8. Search out and identify ANY
single failure where panel display of voltage or
current at any point in the system would be
useful to the pilot in terms of producing a
sure, simple response and graceful recovery.
If a heretofore unconsidered failure/data pair
is identified, what changes could be made to the
design to relieve the pilot of that DISTRACTION
should such a failure occur? We're not treating
pilots like potential idiots. We're doing all we
can BEFORE THE AIRPLANE IS BUILT to reduce risk
of diverting the pilot's time and attention from
the most critical tasks. MOST important, we're
combing the system design, materials and processes for
risk of failure from which no graceful recovery
is possible. This unfortunate condition is more
likely to arise from lack of attention to process
than from a lack of panel displays of real-time data.
The proportion of airplanes bent and people broken
rooted in electrical system failures is VERY small.
Of those cases, the outcomes would have been
strikingly different if failure tolerance were
improved, pilot workload were reduced, and/or
pilot understanding were enhanced. It's my
confident wager that the outcome of any such
incident would NOT have improved by putting
more numbers up on the panel.
Bob . . .
Message 3
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| Subject: | Re: PolyFiber silver coats and their effect on radio |
signals
Today, I did tests to see if the aerials function as I would wish, and
they did. The PolySpray coats appear to have made no difference to
the signals -- even the presumably very small GPS signal.
Great data point sir. Thanks for investigating and
sharing your discovery. I'll capture and archive this
note on the website.
Bob . . .
Message 4
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| Subject: | PolyFiber silver coats and their effect on radio |
signals
> Gents=2C
> I had been wondering=2C for some time=2C what to do about the PolyFiber
> PolySpray coats. PolySpray is a metal-loaded paint that is used to
> protect PolyFiber fabric from UV damage.
>
> FWIW!
>
> James
James=2C
In addition to the information you just shared regarding PolySpray=2C I t
hought I'd throw my two cents in......
Back when I had my Cessna=2C which spent all of it's life outside=2C I no
ticed that the top-side of the surfaces oxidized a fair amount. The wings'
upper surfaces=2C fuselage=2C etc=2C really needed those polishes and wax
jobs.
The bottom surfaces didn't!!!! They were as shiny as the day they got
painted. A wash and a simple coat of wax to clean any smog residue and th
ey were "good to go"!
The tops required plenty of polish and elbow grease!! I was able to even
tually get a pretty decent shine on the top=2C but it was real evident that
it oxidizes "significantly" more than the bottom surfaces (the paint job w
as about 7 years old=2C the underside has ZERO oxidation).
So!! With this personal experience on my own Cessna=2C I made the decisi
on to only spray the Poly Spray silver paint on the upper surfaces of the a
irplane I'm building. The sun does NOT shine on the bottom=2C so I did't w
ant to waste the paint.
I know what the Poly Fiber manual says. It wants you to spray the entire
plane!! I talked to Dondi Miller (@ Aircraft Tech Support...a leading sel
ler of the P.F. products)=2C and she said as far as she knew=2C you have to
spray the entire plane. But=2C since I get to make the decision on my own
plane....I chose not to. Others opinions may differ. I'm ok with that.
What this may have to do with your post is=3B if a guy were planning to
install his antennas inside his Poly Fabric covered plane=2C he might serio
usly consider NOT spraying the Poly Spray silver coats on the bottom surfac
es.
The Poly Fiber manual suggests that in order to get the best UV protectio
n=2C you need to spray the silver coatings thick enough that virtually zero
light shines through. Plus=2C according to the manual=2C a certified airc
raft HAS to be fully covered!!
I can see where such a semi-solid layer of aluminum flakes could affect s
ome radio waves. I chose to not do the bottom surfaces. (They got their s
hare of sealer/paint=2C etc)
Just my thoughts on the matter....
Mike Welch
Kolb MkIII
_________________________________________________________________
The New Busy is not the too busy. Combine all your e-mail accounts with Hot
mail.
http://www.windowslive.com/campaign/thenewbusy?tile=multiaccount&ocid=P
ID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_4
Message 5
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| Subject: | PolyFiber silver coats and their effect on radio |
signals
> I can see where such a semi-solid layer of aluminum flakes could
> affect some radio waves. I chose to not do the bottom
> surfaces. (They got their share of sealer/paint, etc)
Perhaps some consideration of electro-magnetic wave behavior
is useful here . . .
If you were to seal yourself up in a 55-gallon drum
and weld the lid on. A hand held vhf radio would be
useless in terms of communicating with the
outside world. If you added a hole in the drum (but
didn't stick the antenna through the hole), the hole
would have to be enlarged to about 10% of a wavelength
(120 MHz is 2.5 meters or 100 inches. 10% is about
10 inches) to have significant communication with the
outside world but would become really "transparent" at
50% or 50 inches in diameter.
Now consider the effects of suspending particles of
aluminum, probably less than .001" in diameter, in
the path between a transmitting and receiving antenna.
These tiny "shields" are about 1/100,000th of a
wavelength at VHF comm frequencies and 1/10,000th
at transponder frequencies. They are a SIGNIFICANT
part of a wavelength at the frequency of light and
thus offer useful attenuation by reflection of the
effects of light on the surface.
The only way you can make these particle a useful
tool for affecting VHF radio is to electrically bond
the particles together such that the sheet resistance
approaches that of a solid material like aluminum
skin. This simply cannot and does not happen when
dispersed throughout a fluid polymer intended to
be a component of paint.
Some of you may recall a discussion I had with
Greg Richter some years ago wherein he offered
that spray-on conductive coatings were suitable
for adding a ground plane to the inside surface of
a non-conducting skin. There too we considered the
exceedingly difficult task of purposefully increasing
conductivity of an applied coating. In the case
of PolyFiber coatings, there's no interest whatsoever
in the electrical conductivity of the finished
coating.
It's the size of aluminum particles compared with
the wavelength of ultra-violet light that makes
the coating magic . . . it's effectiveness as
a conductor at radio frequencies is very low
and as demonstrated . . . not noticeable in terms
of antennas buried under the skin.
Bob . . .
Message 6
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| Subject: | High Definition MotorSports camera for your aircraft |
Hey guys we are now selling the MSR-200 High Definition MotorSports camera this
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This rugged, weatherproof system is ideal for use in open cockpit vehicles like
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Mount on windshields or mounted on the exterior panels. This is a really nice thing
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--------
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We chrome fiberglass spinners and more!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=300222#300222
Message 7
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| Subject: | Re: PolyFiber silver coats and their effect on radio |
signals
So all those decals on FAA-PMA GPS and transponder antenna radomes saying
"Antenna: Do Not Paint" are flooby-dust, as I long suspected... good to
know.
On Sun, Jun 6, 2010 at 12:53 PM, Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
> nuckolls.bob@aeroelectric.com>
>
>
> I can see where such a semi-solid layer of aluminum flakes could affect
>> some radio waves. I chose to not do the bottom surfaces. (They got their
>> share of sealer/paint, etc)
>>
>
> Perhaps some consideration of electro-magnetic wave behavior
> is useful here . . .
>
> If you were to seal yourself up in a 55-gallon drum
> and weld the lid on. A hand held vhf radio would be
> useless in terms of communicating with the
> outside world. If you added a hole in the drum (but
> didn't stick the antenna through the hole), the hole
> would have to be enlarged to about 10% of a wavelength
> (120 MHz is 2.5 meters or 100 inches. 10% is about
> 10 inches) to have significant communication with the
> outside world but would become really "transparent" at
> 50% or 50 inches in diameter.
>
> Now consider the effects of suspending particles of
> aluminum, probably less than .001" in diameter, in
> the path between a transmitting and receiving antenna.
> These tiny "shields" are about 1/100,000th of a
> wavelength at VHF comm frequencies and 1/10,000th
> at transponder frequencies. They are a SIGNIFICANT
> part of a wavelength at the frequency of light and
> thus offer useful attenuation by reflection of the
> effects of light on the surface.
>
> The only way you can make these particle a useful
> tool for affecting VHF radio is to electrically bond
> the particles together such that the sheet resistance
> approaches that of a solid material like aluminum
> skin. This simply cannot and does not happen when
> dispersed throughout a fluid polymer intended to
> be a component of paint.
>
> Some of you may recall a discussion I had with
> Greg Richter some years ago wherein he offered
> that spray-on conductive coatings were suitable
> for adding a ground plane to the inside surface of
> a non-conducting skin. There too we considered the
> exceedingly difficult task of purposefully increasing
> conductivity of an applied coating. In the case
> of PolyFiber coatings, there's no interest whatsoever
> in the electrical conductivity of the finished
> coating.
>
> It's the size of aluminum particles compared with
> the wavelength of ultra-violet light that makes
> the coating magic . . . it's effectiveness as
> a conductor at radio frequencies is very low
> and as demonstrated . . . not noticeable in terms
> of antennas buried under the skin.
>
>
> Bob . . .
>
>
Message 8
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| Subject: | Re: PolyFiber silver coats and their effect on radio |
signals
Mike Welch wrote:
<snip>
> I know what the Poly Fiber manual says. It wants you to spray the
> entire plane!! I talked to Dondi Miller (@ Aircraft Tech Support...a
> leading seller of the P.F. products), and she said as far as she knew,
> you have to spray the entire plane. But, since I get to make the
> decision on my own plane....I chose not to. Others opinions may
> differ. I'm ok with that.
I almost let this go without comment. It's your plane and you can do as
you chose, but remember that Steve Wittman and his wife were killed
because of not following the Poly Fiber process. Steve probably designed
built more aircraft that anyone I know of. The process was developed for
a reason, and I will follow it.
I just was to make sure that others have this information. You are free
to do what you want with your aircraft, but I will bet that if you did
have an accident caused by not following the process, that your
insurance would be worthless.
Just my $0.02,
Dennis
<snip>
> Mike Welch
> Kolb MkIII
--
Dennis Golden
Golden Consulting Services, Inc.
Message 9
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| Subject: | Re: PolyFiber silver coats and their effect on radio |
signals
At 12:55 PM 6/6/2010, you wrote:
>So all those decals on FAA-PMA GPS and transponder antenna radomes
>saying "Antenna: Do Not Paint" are flooby-dust, as I long
>suspected... good to know.
Not too fast . . . while the effects of the suspended conductive
material has only a small effect on the intensity of passage/
reflection of a signal at radio frequencies, the effect is not ZERO.
In terms of first order effects, it might even be exceedingly
difficult to measure. However, there are also BENDING or LENS
effects to consider.
Radar transmits energy in the hundreds to thousands of watts
while expecting to see very tiny reflections of that energy from
far objects. Further, the DIRECTION from which those signals
are perceived to come is important in deducing the location
of radar-painted object.
Even pure insulators will bend the direction of a radio
frequency wave front not unlike the manner in which a prism bends
light as a function of its frequency (color). While painting
a radome may have little effect on the strength of a
passing signal, it can have a profound effect on changing
the direction of the wavefront. I would think that coatings
carrying conductive particulates would be even worse.
I can tell you that it's an exceedingly difficult task
to craft an "optically perfect" radome that's also friendly
to airflow over the nose of an aircraft. The act of painting
an otherwise optimized radome could have an effect on quality
of the targets display not unlike viewing an object through
a glass brick.
But yes, for non-directional interpretation of received
energy like GPS, Transponders, etc. the effects of additional
paint are very tiny indeed.
Bob . . .
Message 10
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Hi Bob,
I have been flying a Rutan VariEze for many years with several changes in
com antennas. All have been suboptimal. I am planning on mounting a dipole
in the wing-winglet with ferrite donuts at the coax as used with the copper
tape antennas. The plan is to use a length of copper tubing for each leg of
the dipole and thread it up the leading edge of the winglet in the
underlying styrafoam and horizontally in the leading edge of the wing foam. The
center coax lead will be connected to the vertical winglet pole and the
shield to the horizontal wing pole. I was planning on using 1/8 inch copper
tubing. Would that size tubing give me adequate bandwidth? Do you see any other
pitfalls in this plan? I want to make sure it will work before I cut the
2-3 inch hole in the wingtip-lower winglet junction in order to thread the
tubing in and connect the coax.
John Greaves
VariEze N81JG
Redding, CA
Message 11
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| Subject: | Voltage regulator/dropper |
I have built a timer kit for my transfer fuel pump (CK158B from
CanaKit.com) that works as desired. The directions indicate that it
should be powered by 9 Vdc supply or a 12 Vdc 'regulated' supply. I my
electrically dependent plane, I will be using 2 AGM batteries powered by
2 alternators (55A from Geo Metro) converted to external Ford regulators.
I need to build a circuit to drop the 13 to 15 Volts to 9-12 volts,
so as to not zap the HEF4541BP timer IC or 9V relay coil. On my lab
supply, the ammeter doesn't register any perceptible current (it can
show as little as 0.1 amp) while the timer is running with the relay
energized, so I don't know the actual current draw of the timer.
Can you suggest a regulator circuit that will drop the extra 4-5 volts,
and keep the electronics from frying?
Phil in IL, RV-10 w/20B Mazda
Message 12
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| Subject: | voltage regulator level change? |
I have purchased 2 Ford 166 regulators to provide external regulation
(and OV protection capabilities) for the 2 alternators in my
electrically dependent plane.
As I am using AGM batteries, I understand they prefer a higher
charging voltage than standard lead-acid types. Can one readily modify
the Ford regulators to provide the 14.5 V output level? Or, is there an
external circuit that I can insert between the alternator and regulator
(a voltage divider) that would accomplish this?
Phil in IL
Message 13
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At 08:17 PM 6/6/2010, you wrote:
>Hi Bob,
>
>I have been flying a Rutan VariEze for many years with several
>changes in com antennas. All have been suboptimal. I am planning on
>mounting a dipole in the wing-winglet with ferrite donuts at the
>coax as used with the copper tape antennas. The plan is to use a
>length of copper tubing for each leg of the dipole and thread it up
>the leading edge of the winglet in the underlying styrafoam and
>horizontally in the leading edge of the wing foam. The center coax
>lead will be connected to the vertical winglet pole and the shield
>to the horizontal wing pole. I was planning on using 1/8 inch copper
>tubing. Would that size tubing give me adequate bandwidth? Do you
>see any other pitfalls in this plan? I want to make sure it will
>work before I cut the 2-3 inch hole in the wingtip-lower winglet
>junction in order to thread the tubing in and connect the coax.
What kinds of antennas have you tried so far?
What's your criteria for judging them sub-optimal?
Are there other VariEze builders who have already
built the antenna you propose? Have THEY made any
Antenna A versus Antenna B comparisons that would
encourage you to carry out this surgery on the
airplane?
What is the height of the winglet? Can you get
a half-wave radiator up the winglet? There's
a unique center-fed half-wave that runs a
feedline up the center of the lower element.
See:
http://www.miracleantenna.com/AirWhip.htm
This might be easier to install. But
before you start carving on the airplane,
it would be useful to calibrate your
expectations against the physics of
contemporary airborne antenna performance.
Bob . . .
Message 14
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Hi Bob,
I originally had a foil dipole with 20.3 inch limbs and 3 ferrite donuts on
the coax that worked reasonably well until I had to change my brake lines
from Nyloseal to aluminum. That detuned and ruined the antenna. Next I had
a similar tape dipole on the seat back, but my body detuned that. Now I
have the Miracle Whip inside the front fuselage that works within a few 10's
of miles(OK only for inside airport areas), but is too directional probably
due to metal and my legs nearby. Other VE's have had these wing-winglet
dipole antennas and I think they have been satisfactory and I think superior
to all other buried antennas, but I am waiting for reply on the canard
aviators site. The surgery on the plane is minimal since I have a wire conduit
in the foam wing from root to the tip just under the fiberglass tip that I
can access easily and also thread the copper tubing in the foam from.
The winglet height is adequate for the 20.3 inch vertical limb. I would use
the Miracle Whip, but it is too long for the winglet height. I considered
extending it along the outer wing foam with the last 1/2 of the tip in the
vertical part of the winglet, but that would require quite a bit of surgery
to bury the base load box in the wing foam near the center of the wing and
might compromise the foam-skin stress structure of the wing( a definite no
go there option).
I could go to an external whip antenna with a ground plane of wire or
aluminum, but I would prefer not to add parasitic drag. The wingtip idea is less
invasive surgery.
Thanks for your reply. I hope I have answered you questions.
John Greaves
In a message dated 6/6/2010 8:45:31 P.M. Pacific Daylight Time,
nuckolls.bob@aeroelectric.com writes:
At 08:17 PM 6/6/2010, you wrote:
Hi Bob,
I have been flying a Rutan VariEze for many years with several changes in
com antennas. All have been suboptimal. I am planning on mounting a dipole
in the wing-winglet with ferrite donuts at the coax as used with the copper
tape antennas. The plan is to use a length of copper tubing for each leg
of the dipole and thread it up the leading edge of the winglet in the
underlying styrafoam and horizontally in the leading edge of the wing foam. The
center coax lead will be connected to the vertical winglet pole and the
shield to the horizontal wing pole. I was planning on using 1/8 inch copper
tubing. Would that size tubing give me adequate bandwidth? Do you see any
other pitfalls in this plan? I want to make sure it will work before I cut the
2-3 inch hole in the wingtip-lower winglet junction in order to thread the
tubing in and connect the coax.
What kinds of antennas have you tried so far?
What's your criteria for judging them sub-optimal?
Are there other VariEze builders who have already
built the antenna you propose? Have THEY made any
Antenna A versus Antenna B comparisons that would
encourage you to carry out this surgery on the
airplane?
What is the height of the winglet? Can you get
a half-wave radiator up the winglet? There's
a unique center-fed half-wave that runs a
feedline up the center of the lower element.
See:
_http://www.miracleantenna.com/AirWhip.htm_
(http://www.miracleantenna.com/AirWhip.htm)
This might be easier to install. But
before you start carving on the airplane,
it would be useful to calibrate your
expectations against the physics of
contemporary airborne antenna performance.
Bob . . .
(http://www.matronics.com/Navigator?AeroElectric-List)
(http://www.matronics.com/contribution)
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