Static noise from rain or snow
Heinz Bolli
raining or at snowfall.
Has somebody experience what I can do against it?
73 de Heinz, HB9KOF
heinz...@hbag.ch
Jack Malone
lines in area or the arc over on insulators on these lines.
Jack, W7EJJ
"Heinz Bolli" <heinz...@hbag.ch> wrote in message
news:8ukcs6$1d8$1...@bw107zhb.bluewin.ch...
CAM
>
> With my new Sommer XP708-Beam Antenna I have broadband nois up to s9 when
> raining or at snowfall. Has somebody experience what I can do against it?
This is a common problem and also applies to dust storms. An RF choke
or a DC-short balun helps.
--
http://www.mindspring.com/~w6rca
Brian Kelly
Heinz Bolli wrote:
> With my new Sommer XP708-Beam Antenna I have broadband nois up to s9 when
> raining or at snowfall.
>
> Has somebody experience what I can do against it?
>
> 73 de Heinz, HB9KOF
> heinz...@hbag.ch
>
There's lotsa experience amongst the diehard contesters with precip static.
One widely used trick is to run a wire receiving antenna all over the inside
of the house and just keep crankin'. Loop-based antennas like quads do not
suffer the problem.
>
w3rv
J1aguiar
>From: Brian Kelly ke...@dvol.com
>Date: 11/11/00 6:28 PM Eastern Standard Time
>Message-id: <3A0DE411...@dvol.com>
ohm coax, and had many instances when static charges would build up on the coax
inside the house. So bad it was impossible to get near the coax as these blue
balls of fire would strike out at me. I solved the problem by installing a
gamma match to the driven element " plumbers delight", the driven element was
now at ground dc ground. Jim
Brian Kelly
J1aguiar wrote:
> >
> Some years ago I had a three element Cubex quad using a Q match, lengh of 72
> ohm coax, and had many instances when static charges would build up on the coax
> inside the house. So bad it was impossible to get near the coax as these blue
> balls of fire would strike out at me.
>
I never saw anything like that, musta been a whole bunch of fun!
>
> I solved the problem by installing a
> gamma match to the driven element " plumbers delight", the driven element was
> now at ground dc ground. Jim
>
OK, good. I'm about to become a quadhead and this is good input. I think Cecil also
has a good solution with his RF choke suggestion.
>
w3rv
greg
of 72
> > ohm coax, and had many instances when static charges would build up on
the coax
> > inside the house. So bad it was impossible to get near the coax as these
blue
> > balls of fire would strike out at me.
>
i had 1/4" arc's comming off of a vhf/uhf discone during a heavy snowfall
that's why i like my DC grounded antennas or baluns
J1aguiar
>Message-id: <3A12ACFC...@dvol.com>
>
>
>
>J1aguiar wrote:
>
>> >
>> Some years ago I had a three element Cubex quad using a Q match, lengh of
>72
>> ohm coax, and had many instances when static charges would build up on the
>coax
>> inside the house. So bad it was impossible to get near the coax as these
>blue
>> balls of fire would strike out at me.
>
>>
>>
>
>> I solved the problem by installing a
>> gamma match to the driven element " plumbers delight", the driven element
>was
>> now at ground dc ground. Jim
>
>>
>OK, good. I'm about to become a quadhead and this is good input. I think
>Cecil also
>has a good solution with his RF choke suggestion.
>>
>w3rv
>
concerned a quad out performs a yagi when the going gets touch and they work a
lot better than a yagi at the lower hieght. I would however suggest using a
gamma match on the quad. Perhaps Cecil has a better solution to keeping that
static charge under control, but for me the fix was easy and made impedance
matching a snap. Jim
Tom W8JI
>i had 1/4" arc's comming off of a vhf/uhf discone during a heavy snowfall
>
>that's why i like my DC grounded antennas or baluns
If the arc is corona, it won't matter if the element is dc grounded or
not.
Corona comes from the charge gradient between earth and the area
around the antenna.
SHAPE of the antenna, where the antenna doesn't have sharps points
sticking up in the open, reduces corona by increasing distribution of
charges along the surface of the antenna. In some cases, this can
reduce noise during storms.
DC grounding prevents arcs internal to the feedline and antenna, not
external. The main effect of lack of DC grounding is occasional
"pops" as something in the matching system, feedline, or antenna
breaks down.
Quads are quieter only for two reasons. They often don't have a sharp
point sticking way out in space, instead having a long length of
wire. They also generally have a lower impedance part of the antenna
exposed to the strong electric fields where corona occurs. These
effects reduce the amount of "rain or snow static".
Any antenna can be cured of the "DC ground" defect by adding a leak
resistance or choke across the feedpoint. Curing corona requires only
a change in height or shape.
73 Tom
Richard Harrison
"Any antenna can be cured of the "DC ground" defect by adding a leak
resistance or choke across the feedpoint."
Sounds right to me, if one of these points is returned someway to
ground.
Ed Laport in "Radio Antenna Engineering' says the way to eliminate the
noise of small charged particles contacting the antenna and lead-in
wires to discharge is to use wires with sufficient insulation to inhibit
the sudden discharge.
Best regards, Richard Harrison, KB5WZi
Reg Edwards
potential with respect to ground. If the antenna is allowed
to float by insulating it from ground it will aquire a
potential above ground equal to the average. The noise
level impinging on the antenna will then be minimised.
A thickly insulated antenna wire, such as the inner
conductor of a coaxial line plus the polyethylene, will be
less noisy. Probably needs a few inches of pruning to
maintain the same electrical length as an uninsulated thin
wire.
----
Reg
Richard Harrison
"Don`t work! When I designed Razor Beams, I used insulated wire for quad
elements and all yagi elements were grounded to the beam and tower."
Glad you got some relief from precipitation static with an umbrella
effect. I visited with Ed Laport when he was RCA International`s chief
engineer. I was favorably impressed. Ed put in receiving stations as
well as transmitting stations worldwide. He llikely had much experience
with precipitation static. I had no serious precipitation static in my
experience with receiving stations. Guess I was working in better
climates. I`d bet Ed was speaking from experience in his book.
I can imagine a charged particle separating from a cloud producing a
tiny capacitor with a growing separation between its plates. Lessee, Q =
CE. or E = Q / C. As our charged particle moves away from its other
plate, C shrinks while Q is fixed and E soars. By the time it lands on
something it can produce quite a pop when it discharges unless there is
a really hefty insulation to prevent immediate discharge.
Ed didn`t say how much insulation was enough in "Radio Antenna
Engineering". Reg Edwards suggested coax without the shield as possibly
suitable.
Maybe Yuri`s quad elements might have been more immune to precipitation
static with heavier insulation. I haven`t a clue as to how much is
enough. Maybe there are other reasons the static kept coming on Yuri`s
insulated antenna elements. Reg Edwards had another suggestion, to let
the antenna float above ground acquiring a high charge to repel rather
than attract particles. Would that bring on the blue balls of fire?
There probably are many stories of success and failure in the attempt to
eliminate precipation static.
Best regards, Richard Harrison, KB5WZI
Yuri Blanarovich
>Ed Laport in "Radio Antenna Engineering' says the way to eliminate the
>noise of small charged particles contacting the antenna and lead-in
>wires to discharge is to use wires with sufficient insulation to inhibit
>the sudden discharge.
>
>Best regards, Richard Harrison, KB5WZi
>
>
>
>
>
Don't work!
When I designed Razor Beams, I used insulated wire for quad elements and all
yagi elements were "grounded" to the boom and tower, all at the ground
potential (DC). When rain or snow static came, there was that 20 over S9 hash
on the top antenna. Same as on "crumy" TH6. But when I switched to bottom one,
it was dead silence (form static hash). They were both "grounded" on the same
tower.
It appears that top antenna acts as an umbrella for static charge. That was the
only way I could "ignore" the rain/snow static.
When talking about discharge from static electricity buildup, of course you
need things grounded directly or via chokes/resistors/stubs.
Yuri, K3BU
Tesla RC N2EE
Yuri Blanarovich
>eliminate precipation static.
>
>Best regards, Richard Harrison, KB5WZI
>
Possible.
There are basically two problems with "precipitation static." One is a grounded
or unchoked antenna acquiring static electricity charge and then arcing over to
something. (That is easily solved with draining choke or resistors.) The second
one is wideband noise caused by charged particles (snow, rain) hitting metallic
things, having to discharge themselves and creating the hash, regardless of
antenna, it shows up as about 20 over S9.
We had this happen during WRTC in Slovenia for about 8 hours, virtually
paralyzing our reception. We were not allowed to have another antenna, even
piece of wire lying on the ground.
It appears that this hash is caused by discharge of the droplets on metallic
and grounded things, antenna then picks them up (it is right there in the
middle of it). We had discussions on of the reflectors about the phenomena and
mechanics of it (I forgot what was the conclusion, would have to look it up.)
The only 100% working solution seem to be, when you have stacked antennas, or
two layers (high and low) of antennas, only the bottom ones are DEAD quiet, top
or side positioned antennas are overwhelmed by hash.
Based on that experience I would guess that even having HV insulated wires way
up there would pickup "signals" from the droplets being discharged on
(metallic) things "up there." Maybe Laporte was playing with insulated rhombics
on wooden poles? That would probably work, but metallic things in today's
antennas are almost unavoidable, so I doubt that HV insulation would help, the
hash is generated right inside of antenna. It didn't help with Razors, which I
was trying to achieve and failed miserably :-)
Yuri, K3BU
Tom W8JI
>It appears that this hash is caused by discharge of the droplets on metallic
>and grounded things, antenna then picks them up (it is right there in the
>middle of it). We had discussions on of the reflectors about the phenomena and
>mechanics of it (I forgot what was the conclusion, would have to look it up.)
>The only 100% working solution seem to be, when you have stacked antenn
In my experience, and I have plenty with towers as tall as 300 feet,
the bulk of the noise comes from corona discharge.
If the antenna has rounded blunt edges that don't stick out into the
air, it is less affected by incliment weather.
I have problems with "rain static" even when the rain isn't here, just
because the voltage gradient between the antenna and sky increases.
I've found the same thing as Yuri, the only real cure is to mount the
antenna lower, so some other higher conductive object shields it, and
provides the discharge path into the air.
I even did an experiment, charging a water hose outlet with a very HV
supply, and spraying an "antenna" with a fog. The drops themselves
made no noise that I could detect, but getting the cloud near the
antenna end caused corona.
If you listen closely to rain staic (or snow static) during a storm,
you'll hear it build up into a high pitched high level peak, then when
lightning hits anywhere in the area it totally and immediately stops.
You also find that rain or snow MISSING the top antenna and stricking
the bottom antenna will NOT cause any noise at all in cases wher the
antenna is mounted lower on the tower. If the charges were in the
droplets, and transferred to the antenna by the contact...this would
clearly not be the case.
73 Tom
Mark Keith
>
> >There probably are many stories of success and failure in the attempt to
> >eliminate precipation static.
> >
> >Best regards, Richard Harrison, KB5WZI
> >
>
> Possible.
> There are basically two problems with "precipitation static." One is a grounded
> or unchoked antenna acquiring static electricity charge and then arcing over to
> something. (That is easily solved with draining choke or resistors.) The second
> one is wideband noise caused by charged particles (snow, rain) hitting metallic
> things, having to discharge themselves and creating the hash, regardless of
> antenna, it shows up as about 20 over S9.
> We had this happen during WRTC in Slovenia for about 8 hours, virtually
> paralyzing our reception. We were not allowed to have another antenna, even
> piece of wire lying on the ground.
> and grounded things, antenna then picks them up (it is right there in the
> middle of it). We had discussions on of the reflectors about the phenomena and
> mechanics of it (I forgot what was the conclusion, would have to look it up.)
> two layers (high and low) of antennas, only the bottom ones are DEAD quiet, top
> or side positioned antennas are overwhelmed by hash.
> Based on that experience I would guess that even having HV insulated wires way
> up there would pickup "signals" from the droplets being discharged on
> (metallic) things "up there." Maybe Laporte was playing with insulated rhombics
> on wooden poles? That would probably work, but metallic things in today's
> antennas are almost unavoidable, so I doubt that HV insulation would help, the
> hash is generated right inside of antenna. It didn't help with Razors, which I
> was trying to achieve and failed miserably :-)
>
> Yuri, K3BU
Hummmm, that seems weird to have the bottom antennas quiet if the cause
is wideband noise caused by charged particles. Seems this would effect
the bottom antennas also if this was the case. I've had this noise many
times, and have tried things like quickly grounding the antenna and then
switching back to it real fast to see if the noise changed. It never
seemed to make any difference. So it didn't seem to be from any built up
charge on the antenna wires that could be discharged to lower the noise.
I would just have to wait it out. I would notice many times the noise
did seem to build up though. It would "tick" faster and faster as if
something in the area was indeed building a charge up and arcing to
something. I'm wondering...maybe you were streaming as in lightning.
This would explain why the lower antennas were quiet. The top antenna
acts as the lightning rod, and streams, where the lower one doesn't.???
If this is the case, it would seem to me that adding a lightning rod
above the top beam should make it quieter also, unless you are receiving
rf from arcing. I'm not sure if insulated wire helps any at all. Maybe a
bit, but I think I still get the noise with the insulated wire. All my
present wire antennas are from #12 insulated copper wire. I'm guessing
the insulation good for 600 volts +-??? .So anyway, maybe trying a
lightning rod above the top beam would help it. Worth a try maybe..Also
I would think if something in the area is streaming it would generate
noise that could be heard in the receiver. After all, it's an arc of
sorts. Should be noise from dc-light nearly I would think. MK
--
http://web.wt.net/~nm5k
Mark Keith
>
> If you listen closely to rain staic (or snow static) during a storm,
> you'll hear it build up into a high pitched high level peak, then when
> lightning hits anywhere in the area it totally and immediately stops.
> You also find that rain or snow MISSING the top antenna and stricking
> the bottom antenna will NOT cause any noise at all in cases wher the
> antenna is mounted lower on the tower. If the charges were in the
> droplets, and transferred to the antenna by the contact...this would
> clearly not be the case.
>
> 73 Tom
I hadn't seen your post before I posted the other one, but your
experience seems to agree with my theory of this noise being streamer
related. Or corona disharge, which in that case would be almost the
same. I've also heard the noise that goes away with a lightning
strike."usually a ticking type sound that varies with speed" That's what
led me to believe I was hearing "streamers" off in distance. Maybe not
too far away either. So maybe the best thing to kill noise, might not be
a lighting rod, but maybe the opposite, a large blunt ball like a flag
pole. Anyway, these theories make more sense to me than charged
particles hitting the antenna. If that were true, I'd expect all levels
to have about the same noise. MK
--
http://web.wt.net/~nm5k
Yuri Blanarovich
>lightning rod above the top beam would help it. Worth a try maybe..Also
>I would think if something in the area is streaming it would generate
>noise that could be heard in the receiver. After all, it's an arc of
>sorts. Should be noise from dc-light nearly I would think. MK
>--
>http://web.wt.net/~nm5k
>
It doesn't, I had Ringo ranger 2m vertical, which is basically grounded
"lightning rod" on the top of the tower, tip being about 20 ft up from the 62ft
boom on the Razor and it did nothing for suppressing the hash.
The only thing that works is the lower antennas, below another set of antennas
higher up.
When you think about it, the top antenna (say at 100 ft) gets hash at 20 over 9
(just about standard signal level regardless of antennas used), while lower
antenna (say at 50 ft) gets NOTHING, zilch, absolutely quiet with no traces of
hash. You would think that Hash "signal" 50 ft higher would be also "heard" by
the lower antenna, but it isn't!
Now the quantum scientwists can speculate what is going on.
Saw interesting quote the other day (I hope it is not copyrighted :-)
"Never be afraid to try something new;
remember amateurs built the Ark,
professionals built the Titanic"
Yuri, K3BU
Tesla RC N2EE in CQ WW CW on 10m
Dick Carroll
>
> If you listen closely to rain staic (or snow static) during a storm,
> you'll hear it build up into a high pitched high level peak, then when
> lightning hits anywhere in the area it totally and immediately stops.
> You also find that rain or snow MISSING the top antenna and stricking
> the bottom antenna will NOT cause any noise at all in cases wher the
> antenna is mounted lower on the tower. If the charges were in the
> droplets, and transferred to the antenna by the contact...this would
> clearly not be the case.
Early in my much-noted experience as a Highway Parol radio op we used a
1/4 wave ground plane antenna mounted atop a 350 ft freestanding tower,
with the active element insulated from ground in the conventional
manner. Often when a storm involving turbulence would move into the
area, the three FM 42 mHz receivers squelches would come open and the
static would build to a howling cresendo, after which either there was
an 'snap', an arc which discharged things or lightning would strike.
Theniet would start again, and would repeat several times during a given
storm, until the turbulance passed out of the area. The static would
desense the recievers so much that it was not possible to receive a car
from even a few miles distance while it was happening.
Later the ground plane antenna system was replaced with a colinear type
consisting of four folded dipoles mounted on each tower leg, spaced from
the top of the tower down. These antennas operated at DC ground with
respect to the tower. That was the end of the rain static. I never once
heard it on the new colinear antenna.
That antenna system was in use for over 15 years before I got there,
and during turbulent thunderstorms it would virtually paralyze the
receivers. Fortunately such a storm rarely lasted more than a few
minutes.
Dick
Richard Harrison
"Anyway, these theories make more sense to me than charged particles
hitting the antenna."
Terman agrees:
"The term "precipitation static" denotes a type of interference
frequently observed in an airplane passing through snow or rain. Under
such circumstances, the airplane may become electrostatically charged to
such a high potential with respect to the surrounding space that a
corona discharge breaks out at some sharp point on the plane. The
interference that this corona discharge produces with radio reception,
termed "precipitation static" is particularly serious at short-wave and
lower frequencies.
Precipitation static can be minimized by the use of antennas that are
either insulated wires or shielded loops, by equipping the plane with
dischargers that provide a noninterfering means of getting rid of the
charge being acquired by the plane, and locating receiving antennas as
far as possible from the corona discharges."
Mark Keith
>
> >There probably are many stories of success and failure in the attempt to
> >eliminate precipation static.
> >
> >
>
> There are basically two problems with "precipitation static." One is a grounded
> or unchoked antenna acquiring static electricity charge and then arcing over to
> something. (That is easily solved with draining choke or resistors.) The second
> one is wideband noise caused by charged particles (snow, rain) hitting metallic
> things, having to discharge themselves and creating the hash, regardless of
> antenna, it shows up as about 20 over S9.
> We had this happen during WRTC in Slovenia for about 8 hours, virtually
> paralyzing our reception. We were not allowed to have another antenna, even
> piece of wire lying on the ground.
>
> Yuri, K3BU
I've been kicking this around in my head. I think a lightning rod would
cure it. I thought about the ball or ball discharger as some call them,
but seems to me if the antenna streams ok as is, I don't really see how
using a ball in the area would help much except for the tower or mast it
was attached to. It would keep the tower from easily streaming, but
don't think it would keep the antenna from streaming if it would be
inclined to do it anyway. I thought about possible noise from the arcing
of a streamer itself, and maybe that would make things worse, but if you
can have the bottom antenna quiet while the top is streaming, seems to
me you could be fairly close to a "designed streamer" and not have too
bad a noise. So I kind of think adding a lightning rod above the top
antenna would help a lot. The rod would stream much easier than the top
antenna and would be above it a bit. This should "act" as another
antenna above the top one, and make both quiet. I can't try it here, as
don't even have one layer of beam up, much less two, but might be worth
a try for someone who does. MK
--
http://web.wt.net/~nm5k
Brian Kelly
Richard Harrison wrote:
>
Check out any serious aircraft and you'll find what look like little
"probes" with sharp points aimed aft, usually somewhere on the vertical or
horizontal stabilzers or both and occasionally on the ailerons.
>
>
>
> Best regards, Richard Harrison, KB5WZI
>
w3rv
Mark Keith
> >
> Check out any serious aircraft and you'll find what look like little
> "probes" with sharp points aimed aft, usually somewhere on the vertical or
> horizontal stabilzers or both and occasionally on the ailerons.
Hummm, sure those aren't vortex disturbers? Many smaller jets etc use
those. I haven't really noticed the sharp points on too many, but guess
I didn't look too hard. A vortex disturber looks like a short metal
strip sticking up off the wings etc. You will see a whole row of them on
many planes like learjets etc. They would probably look kinda like
little probes from a distance. But, these may be totally different items
from what you describe. I'll have to look into that sometime. The vortex
disturbers do as their name describes. The reason I'm familiar with
these is a friend of mine works on learjets. I went over there one time,
and noticed all those short strips all over the wing, and asked him what
they heck they were. Weird looking little things. But you can tell those
as they just look like a strip of metal like they were cut out with
scissors. MK
--
http://web.wt.net/~nm5k
Mark Keith
> >
> Check out any serious aircraft and you'll find what look like little
> "probes" with sharp points aimed aft, usually somewhere on the vertical or
> horizontal stabilzers or both and occasionally on the ailerons.
Actually, thinking about it, if the ones you describe point aft, they
are probably different from the disturbers. The vortex disturbers point
straight up nearly. MK
--
http://web.wt.net/~nm5k
Mark Keith
>
> Mark Keith wrote:
> "Anyway, these theories make more sense to me than charged particles
> hitting the antenna."
>
> Terman agrees:
> "The term "precipitation static" denotes a type of interference
> frequently observed in an airplane passing through snow or rain. Under
> such circumstances, the airplane may become electrostatically charged to
> such a high potential with respect to the surrounding space that a
> corona discharge breaks out at some sharp point on the plane. The
> interference that this corona discharge produces with radio reception,
> termed "precipitation static" is particularly serious at short-wave and
> lower frequencies.
Many planes will build up a corona that nearly surrounds the jet. Or the
front end anyway. Many times pilots can see the blue glow all around the
windshield, windows etc. Looks pretty wild at night.
>
> Precipitation static can be minimized by the use of antennas that are
> either insulated wires or shielded loops, by equipping the plane with
> dischargers that provide a noninterfering means of getting rid of the
> charge being acquired by the plane, and locating receiving antennas as
> far as possible from the corona discharges."
Huumm, kinda surprised insulated wires would help that much. Doesn't
seem to make a whole lot of difference here on the ground. But then
again, I've never really tested it to compare. All my current ant wires
are insulated, but I still hear the noise from time to time I think. I
don't notice much noise at all from my small 3 el yagi for 2m. But it
has very rounded element ends. It's one of those 2m beams that Alex
sells at City electronics. A very nicely built yagi I think. I think
some friend of his makes them. MK
Fred Hambrecht
to be loose string hanging out the ends. These are used to bleed off static
charges. What you are referring to are Vortex Generators. On the Lear 23
with the original wing they were mounted on both the top and bottom of the
wing. Later models had them only on the top and they were removed entirely
if a MK1 wing was installed. The are a NO GO item if more than 3 are missing
as I recall.
Many times while descending through a snow storm I have seen continuos balls
of blue static emanating from the nose of the tip tank and along the
windshield pillar.
I hold Commercial ASMEL with instrument. Type ratings include LearJet,
Cessna Citation, and DC3 ratings. The old prop jobs use to get rings of
static around the edge of the prop. At 8000 feet in the winter between
Buffalo and Detroit it would be so bright on the old Beech BE8T's it would
light up the cockpit.
"Mark Keith" <nm...@wt.net> wrote in message news:3A183A...@wt.net...
> Brian Kelly wrote:
>
> > >
> > Check out any serious aircraft and you'll find what look like little
> > "probes" with sharp points aimed aft, usually somewhere on the vertical
or
> > horizontal stabilzers or both and occasionally on the ailerons.
>
Tom W8JI
>It doesn't, I had Ringo ranger 2m vertical, which is basically grounded
>"lightning rod" on the top of the tower, tip being about 20 ft up from the 62ft
>boom on the Razor and it did nothing for suppressing the hash.
>The only thing that works is the lower antennas, below another set of antennas
>higher up.
>When you think about it, the top antenna (say at 100 ft) gets hash at 20 over 9
>(just about standard signal level regardless of antennas used), while lower
>antenna (say at 50 ft) gets NOTHING, zilch, absolutely quiet with no traces of
>hash. You would think that Hash "signal" 50 ft higher would be also "heard" by
>the lower antenna, but it isn't!
The reason you can't hear the noise, is the energy of the noise is
very very low. It is caused by tiny corona discharges from the
elements in the antenna. All the charges do is leak off into the air
around the antenna. It isn't a "path" up to the clouds in the sky, if
it was you'd be in deep crap when the ionized air suddenly discharged
the cloud!
That's why a quad is purported to be quieter than a yagi. The corona
on a quad is at a low impedance point, not like a yagi with the tips
of the elements sticking out in the air. The yagi is closer matched to
the exteremly low current high voltage discharge caused by the high
voltage gradient between the earth and the clouds.
The LAST thing you want to do is add more corona near the antenna,
although if you add it higher up it will "neutralize" the charge seen
by the lower antenna and stop it from having corona streamers.
73 Tom
Roger Halstead
N833R World's Oldest Debonair? s# CD-2
"Mark Keith" <nm...@wt.net> wrote in message news:3A183B...@wt.net...
> Brian Kelly wrote:
>
> > >
> > Check out any serious aircraft and you'll find what look like little
> > "probes" with sharp points aimed aft, usually somewhere on the vertical
or
> > horizontal stabilzers or both and occasionally on the ailerons.
Static wicks (they don't normally have sharp points) are just stranded wire
pieces about 4 inches long that trail from the airlerons and elevator. They
are sometimes attached to the rudder and vertical stabilizer as well.
>
> Actually, thinking about it, if the ones you describe point aft, they
> are probably different from the disturbers. The vortex disturbers point
> straight up nearly. MK
The vortex "generators", generally fit along the most curved portion on the
top surface of the wing. These actually keep the air attached to the top of
the wing at speeds below where the air will normally stay attached. This
gives reduced stall speed which may allow for increased gross weight.
Roger (K8RI)
> --
> http://web.wt.net/~nm5k
Roger Halstead
thing to get rid of the noise. Particularly on the nav radios. The ADF is
the most susceptible and the VORs right behind it. I had to restart all the
electronics twice within 20 minutes on one trip
I've not experience any problems with GPS yet, but I've not gotten into any
storms of the magnitude that shut down every radio in the plane prior to
installing GPS so I can't speak about its effects on GPS.
--
Roger Halstead (K8RI) www.RogerHalstead.com
N833R World's Oldest Debonair? s# CD-2
"Mark Keith" <nm...@wt.net> wrote in message news:3A183B...@wt.net...
> Brian Kelly wrote:
>
> > >
> > Check out any serious aircraft and you'll find what look like little
> > "probes" with sharp points aimed aft, usually somewhere on the vertical
or
> > horizontal stabilzers or both and occasionally on the ailerons.
>
> Actually, thinking about it, if the ones you describe point aft, they
> are probably different from the disturbers. The vortex disturbers point
> straight up nearly. MK
> --
> http://web.wt.net/~nm5k
Mark Keith
>
> Two items, one is a static wick, normally black in color with what appears
> to be loose string hanging out the ends. These are used to bleed off static
> charges. What you are referring to are Vortex Generators. On the Lear 23
> with the original wing they were mounted on both the top and bottom of the
> wing. Later models had them only on the top and they were removed entirely
> if a MK1 wing was installed. The are a NO GO item if more than 3 are missing
> as I recall.
Yep, thats right. I don't know how I got disturbers in my head. Been
quite a while. And yep, I think he mentioned the same thing. If a few
missing, you couldn't fly. They had both types of wings also. The newest
one they had the newer wing with no tabs. They had two or three of them
in the hangar when I was there. All were fairly old. The newest one I
think a 35a. Maybe older than that , I forgot...
>
> Many times while descending through a snow storm I have seen continuos balls
> of blue static emanating from the nose of the tip tank and along the
> windshield pillar.
Nothing like your own lightshow to fly with...g MK
--
http://web.wt.net/~nm5k
Mark Keith
>
> BTW, even with static wicks, it's not uncommon to have to turn off every
> thing to get rid of the noise. Particularly on the nav radios. The ADF is
> the most susceptible and the VORs right behind it. I had to restart all the
> electronics twice within 20 minutes on one trip
>
> I've not experience any problems with GPS yet, but I've not gotten into any
> storms of the magnitude that shut down every radio in the plane prior to
> installing GPS so I can't speak about its effects on GPS.
Maybe less effect than the radios. But just guessing. I would think the
higher the freq of the device the less noise problems. ADF being real
low freq would get whacked bad. I don't think I would like to fly in
storms too much. I even try to avoid them flying commercial jets. I had
to take a 737 to Little Rock about a week ago . I waited until all the
t-storms cleared out before I would get on that thing. We had a big line
of them the night before that. Luckily, I timed my reservation just
right, and left Houston with clear wx. Hit rain up north, but no big
deal. Just light stuff. MK
--
http://web.wt.net/~nm5k
Mark Keith
>
> I hold Commercial ASMEL with instrument. Type ratings include LearJet,
> Cessna Citation, and DC3 ratings. The old prop jobs use to get rings of
> static around the edge of the prop. At 8000 feet in the winter between
> Buffalo and Detroit it would be so bright on the old Beech BE8T's it would
> light up the cockpit.
Hummm, I was thinking of something. I could use your expertise on
something if you fly lear's. I've been working on a panel for FS2000
flight sim, for the Lear 31a. I hacked up a few pictures I managed to
get, and am wondering with all the patching if I got the perspective
right, or even close. There is still alot of work to do on the gauges,
so not all are correct. IE: engine gauges need the faces painted, etc,
etc. Still quite a ways to go. I'll post a pix of what I have so far.
It's a jpg with reduced quality to speed the d/l. Only about 78k. Does
the overall perspective look about right, or do I need to zoom in
farther? Also does the cowling look right. I had to hand draw the top of
the cowling to the left, so may not look quite right. Howz it look
overall? Ok, or do I need to start over? BTW, Sorry for this non antenna
subject, but I tried to snare a few lear pilots advice on the sim sites
with no replies. Not enough real pilots around for the lears I guess. MK
--
Click this link for the pix...
Mark Keith
>
> Fred Hambrecht wrote:
>
> http://web.wt.net/~nm5k/31a.jpg
BTW, When flying this thing, I sit a bit to the left, behind the AI-HSI
etc to get the perspective of sitting in the left seat. Kinda cramped on
a puter screen.. MK
--
http://web.wt.net/~nm5k
Fred Hambrecht
could quibble about the location of some of the secondary instruments. But
these are left up to the owner, so no problem I see. The perspective looks
OK to me.
"Mark Keith" <nm...@wt.net> wrote in message news:3A198E...@wt.net...
Mark Keith
>
> Was detailed enough that I wanted to put in a little left rudder trim. One
> could quibble about the location of some of the secondary instruments. But
> these are left up to the owner, so no problem I see. The perspective looks
> OK to me.
Ok, Thanks for the look. Yep, many of the gauges still need alot of
work. The autopilot is wrong and is just pasted in from another panel
for now to be able to fly. The AOA is giving me a problem , as the only
properly working one I have is the round kind you see on a few models. I
want to proper rectagular one but will need to program a new gauge. The
round one just doesn't look right in the 31a. To me anyway..The
secondary A/S, altimeter,AI gauges are in the exact place as the picture
the panel is made from, but I have a slight cutoff up near the top. Need
to redo that I think. You can see the placard is cut off. A problem was
the detailed pix didn't extend up into the A/P and cowling etc. So had
to butcher in those areas from other pictures. The panel picture was
taken from a corporate 31a and was pretty sharp in the original true
color pix, but lost a bit in all the chopping and reduction to 256
color. I may make a 24 bit version, but will take a bit more memory to
run and puts a bigger overhead on the video. Anyway still a ways to
go...I don't know if you mess with the sims, but if you want a copy of
it, let me know. I also have made a pretty detailed kingair 350, and a
couple of panels for C-130. One a glass version, and one the old analog
gauges. I have a few pix of the kingair panel on my server. It's fairly
complete. Thanks again, I don't want to spend half a zillion hours
working on something if it doesn't look right. Also open to any
suggestions on it. :( MK
--
http://web.wt.net/~nm5k/ka350.jpg
fer the big picture
http://web.wt.net/~nm5k/kaquad.jpg
to show the different radio/gps panel pages.
Roger Halstead
N833R World's Oldest Debonair? s# CD-2
"Mark Keith" <nm...@wt.net> wrote in message news:3A198A...@wt.net...
> Roger Halstead wrote:
> >
> > BTW, even with static wicks, it's not uncommon to have to turn off every
> > thing to get rid of the noise. Particularly on the nav radios. The ADF
is
> > the most susceptible and the VORs right behind it. I had to restart all
the
> > electronics twice within 20 minutes on one trip
> >
> > I've not experience any problems with GPS yet, but I've not gotten into
any
> > storms of the magnitude that shut down every radio in the plane prior to
> > installing GPS so I can't speak about its effects on GPS.
>
> Maybe less effect than the radios. But just guessing. I would think the
> higher the freq of the device the less noise problems. ADF being real
> low freq would get whacked bad.
I don't think I would like to fly in
> storms too much. I even try to avoid them flying commercial jets. I had
> to take a 737 to Little Rock about a week ago . I waited until all the
> t-storms cleared out before I would get on that thing. We had a big line
> of them the night before that. Luckily, I timed my reservation just
> right, and left Houston with clear wx. Hit rain up north, but no big
> deal. Just light stuff. MK
I stay well away from thunderstorms, but heavy rain will at times create
lost of statice, but nothing like snow. Really cold "dry" snow creates an
unbelieveable amount of static.
Last Summer I flew the approach into 3BS. We were at 7,000 and had to start
down about 40 miles out. As soon as we entered the clouds (just under
7,000) we were in torrential rain. It was a nice smooth ride and no static
at all. We broke out about 3 miles from the airport. About a mile to
either side of us the ceiling dropped well below minimums. It was like
flying in an inverted canyon.
I had an ungrounded 1/4 wave 40 meter vertical.
We had a strong wind and heavy snow. The end of the RG-8 was disconected
and there was a bright, fat, blue arc that was coming out nearly an inch
before coming back to the shield. It was creating a pop like a small
firecracker. "Quite loud". It would "pop" about every 10 seconds.
I've never seen an ignition system, including the mags on the plane, put
out that hot a spark.
Having gotten nailed on many an ignition system, I left that litter sucker
lay their until the storm was over. After that I grounded both the shield
and center conductor.
Brian Kelly
Mark Keith wrote:
> Brian Kelly wrote:
>
> > >
> > Check out any serious aircraft and you'll find what look like little
> > "probes" with sharp points aimed aft, usually somewhere on the vertical or
> > horizontal stabilzers or both and occasionally on the ailerons.
>
> Hummm, sure those aren't vortex disturbers? Many smaller jets etc use
> those. I haven't really noticed the sharp points on too many, but guess
> I didn't look too hard. A vortex disturber looks like a short metal
> strip sticking up off the wings etc. You will see a whole row of them on
> many planes like learjets etc. They would probably look kinda like
> little probes from a distance. But, these may be totally different items
> from what you describe. I'll have to look into that sometime. The vortex
> disturbers do as their name describes. The reason I'm familiar with
> these is a friend of mine works on learjets. I went over there one time,
> and noticed all those short strips all over the wing, and asked him what
> they heck they were. Weird looking little things. But you can tell those
> as they just look like a strip of metal like they were cut out with
> scissors. MK
>
Trust me, I know the difference between "vortex disturber" strips and static
charge dumpers. Done some fly stuff myself. V-22 Osprey build #3 is parked abt
75ft. from the cube I've been occupying of late and the whole butt end of the
thing is loaded with 3/8" diameter pointy rods aimed aft which toss charges back
where they came from . The last thing Bell or Boeing could give a rat's patooie
about is dressing a V-22 up with vortex disturbers. The damned squirrely
abomination wouldn't get off the ground, which it certainly does, without the
monstrous vortxes it's Allisons generate.
>
w3rv
Mark Keith
>
> I had an ungrounded 1/4 wave 40 meter vertical.
> We had a strong wind and heavy snow. The end of the RG-8 was disconected
> and there was a bright, fat, blue arc that was coming out nearly an inch
> before coming back to the shield. It was creating a pop like a small
> firecracker. "Quite loud". It would "pop" about every 10 seconds.
I had a ten meter 5/8 GP that would do that. But not quite so loud. But
it would arc from center pin to shield about every ten seconds or so
when I had charged clouds going over. No rain or anything. A grounded
coil could have cured that, but I prefered ungrounded as I used that
antenna on 30m also as a 1/4 wave. It's funny, I had the 32 ft 40m
antenna at 36 ft which was longer and higher then the 10m ant and also
ungrounded, but it never arced in any wx. Go figure...:/ MK
Mark Keith
> Trust me, I know the difference between "vortex disturber" strips and static
> charge dumpers. Done some fly stuff myself. V-22 Osprey build #3 is parked abt
> 75ft. from the cube I've been occupying of late and the whole butt end of the
> thing is loaded with 3/8" diameter pointy rods aimed aft which toss charges back
> where they came from . The last thing Bell or Boeing could give a rat's patooie
> about is dressing a V-22 up with vortex disturbers. The damned squirrely
> abomination wouldn't get off the ground, which it certainly does, without the
> monstrous vortxes it's Allisons generate.
> >
> w3rv
Yep, I guess you missed my 2nd post.. I came to the same conclusion
being as they point backwards instead of straight up. Also I was calling
them the wrong name anyway. Should be vortex generators. Yep, the v-22 a
strange animal. I had a model of one of those I tried to rig up for the
sim. It sorta worked ok, not the greatest though. It flew, and you could
change the pitch of the rotors, but it still wasn't too accurate I don't
think. Maybe could do a better one now the the air file technology has
improved a bit. MK
--
http://web.wt.net/~nm5k