P.S.     Further investigation puts the bandwidth for the Laird TRAT1420/TRABT1420 at 1 MHz.

Thanks very much for the info, WB6BYU.  Very helpful link as well!

I want to install a 2-meter rig in my commercial-use vehicle (a Sprinter van) but I can't allow the distracting appearance or the increase in clearance height of a whip antenna.   The vehicle is used in urban circumstances with many repeaters nearby, so the need for long range capabilities is minimal.

I noticed a very compact stub antenna made by Laird (TRAT1420, TRABT1420) listed in AES, but couldn't find any links re performance.

Has anyone out there tried this antenna?  Even the QST archives are silent, which makes it hard to risk the purchase price (<$100.00 US).  But who wants to flush 100 bucks for nothing?

Dave
KF7OAE

KATEKEBO

I share your interest in astronomy and astrophysics (come cosmology), but to a lesser degree at the moment than my focus on EM.  I've got an idea about waveform propagtion that won't let me be.  You said that dark matter is an unknown form of matter that doesn't absorb or emit EM.  To me that means that, even though its not well understood as yet, its not completely unknown.  At least some of its properties are known.  Fascinating stuff.

Aside from that, let me say something more about my theory.  Several layers of the earth's atmosphere act as reflectors of radio waves.   To me that means that if it can be reflected (and to some degree absorbed) by ionized gas in the atmosphere, then it can be detected and interpreted in a useful way by ionized gas containers on the surface for use in radio communications.  I know that much study has been devoted to the concept by people better informed than myself, but I can't let that stop me from looking into the subject independantly.  After all, its a hobby. 

My next effort will be filling a radio-transparent container with argon, minus the dopant inclusions that are used to produce the lightning bolts in the novelty globes that have been around for many years.  I'd like to try some of the less common noble gasses, but an 80 cubic foot tank of purified neon costs about $5,000.00.  I'm not curious enough to sell my Harley.  Yet.

Step by step by step.

KF7OAE

N3OX

Well, Dan, thanks again for the time you took on the last post.  Metamaterials, especially.  The negative index of refraction, and the methods used to produce it, are subjects that will keep me busy for a while.  A very odd lattice fence may appear in my back yard.  Thanks.  Your earlier reference to a double negative plasma shell will also keep me busy for a while.  I'd like to apply the idea to a flat plane instead of a sphere.  But, then, I'd also like to hit Powerball some time soon.

You suggested that refinements in the types of antennas now in use leave a lot of room for improvement, so much so that any radio operator who chases out the details would find that there's no real need for improvement.  I agree, but that's not why I'm doing this.  I'm just attracted to the concept.  Maybe I'm a little obsessive/compulsive.  The antennas I'm using now work quite well.  I may or may not come up withsomething better, but I bet I can do something different.  Besides, its fun.

73s

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AD6KA

Despite your tone, thanks for the input Ken.  Nothing ventured, nothing gained.

By the way, the number of experiments, crude though they have been, is 7.  Some overlapped, but 7 seems about right.  This thing has me by the tail, and I'm here in this forum to see what others might have to say.

I'm serious when I say that I believe there's another way, besides the usual ways, to 'see' radio waves.  I'm looking around for the means to do it.  No commercial motive, no ties to industry.  Just curious.  I've never asked others to do my work for me.  What I'm looking for is a little guidance while I work on this strange thing alone.  Narrows the field a bit when people who know the subject take a moment to mention a little of this or that, here and there.

Plasma may not even be the right medium to achieve my goals.  Its just the tree I'm barking up at the moment.

Anyway, thanks again for the comments, Ken.

73s

KF7OAE

KATEKEBO

Thanks for the input, Slawomir.  As to the percentages of composition of the universe, I suppose it comes down to interpretations.  The Dark Energy (74%) and Dark Matter (22%) you mentioned may have properties that qualify them as forms of plasma, since plasma is just a state, not matter of its own.  There may be room for both sets to be correct.  Matter doesn't have to be highly ionized in the way found in stars to be described as plasma.

I agree, as well, that hot plasma would not be welcome in, around, or near my radio shack in its free state.  The local fire marshal would probably object.  At any rate, the weaker 'cold' plasma is all that's practical to experiment with here in the old back yard.  In my case, I'm just having fun with a thought that won't go away.

KF7OAE

N3OX     Thanks, Dan!  Nice to hear from someone with a Ph.D. in physics who's willing to discuss my interests.  The amateur radio community is lucky to have people like you.

I'm trying to think outside the box a bit.   Antenna technology seems like an area that's overdue for a breakthrough.

In response to your advice about being specific:  The shape and size of the plasma container being used as an antenna would be key in determining how and where it could be applied.  Everything I've come across so far that uses plasma as a medium is spherical in some respect.  I wonder if a flat plane would work?

I see the day when metal towers and large arrays are things we look back on.  I've been sniffing around on this subject for a while now and have found that its well attended.  So, not being in a position to contribute significantly to the theory end, I'd like to throw out the suggestion that amateur operaters such as myself might be able to contribute on another level.  Research in most fields eventually boils down to the tedious process of ruling out possibilities by trying them in direct application.  I would love to be involved in an effort like that.  Building containers of different sizes and shapes, filling them with ionized gasses, applying current, and measuring and recording the results is right up our alley.

Leg work.  Interesting to the point of fascination, educational, and challenging.  Not to mention, with proper guidance, productive.

Just a thought.

KF7OAE

KQ6Q

Thanks for the reply.  Unfortunately, this is an example of conventional RF exchange, albeit through an unconventional media.

 A while ago I scanned a page detailing the use of an oak tree as an antenna!  The author wound a balun around the base of the tree and made the whole tree work as a receiver/transmitter!  I suppose its less of a surprise when you grab the base of a rubber-duck antenna that's fixed to your handheld and experience an improvement in reception.

KF7OAE

N8BOA

Thanks for the reply.  Unfortunately, superconduction occurs at very low Kelvins.  Not practical for common use.

KF7OAE

K6AER

Thanks for the impedance question.  I suppose the answer is in the crux of the question, that being the hugely different properties of plasma.  As mentioned, plasma isn't a substance but rather a state of existence for a wide range of substances.  Each probably has its own impedance values. That's my problem.  The categories of substances that can be included in the definition 'plasma' as a description are many.  Emphasis many.  Which will work best?  How should they be managed for communicatiuon purposes?

As an aside, I (instinctually) believe that the behaviour of plasma when used as an antenna will obviate several conventions, such as resonance and impedance.  I believe that we are looking at the interpretation of waveform energy via a new format.  We've depended on resonance since the days of Tesla, but we are now fooling around with a new media.  I'd describe it as reflection, looking into a new mirror.  I personnaly am fascinated by the possibilities.  Brought to fruition, the double-paned windows in our homes, filled with plasma, have the pontential to replace every bit of aluminum we as radio communications enthusiasts now have hanging in the air.

WS3N

Thanks for the correction.  I regreted the misnomer the minute I posted it.  I'm impressed.  Not many folks would know the difference.  Bose/Einstein condensate is correct.

Thanks very much, Peter.  I've googled the subject, but not through Wikipedia.  Just missed it.  I noticed that the phrase "under developent" appeared more than once in the link.  I wish I had greater reources...I'd 'develop' it too.  Seems there are no good ideas left for guys like me...

The first three being solid, liquid, and gas, with the fourth state (plama) making up about 97% of the known universe.  Its what the stars are made of.  Its important to remeber that it is not a substance of its own, but rather a state of matter.  For instance, water can be either a solid, a liquid, or a gas depending on temperature, etc.  Most materials can be brought to at least two states by common means, i.e., steel can be melted, oxygen can be liquified, etc.  However, a fourth state is available.  Actually, a fifth state has also recently been proven, that being the Bach/Einstein condensate, but its of no value in this discussion.

So, here's my concept, and thanks for staying with me through the preamble.  I believe that plasma of the right type trapped in the right container should be able to act as an antenna.  Its generally reactive to waveform energy in a big way, and I believe that its reactivity should be measurable and interpretable for use in radio communications.  Several advantages over current antenna types would occur if the concept were brought to fruition.

My question to the reader of this posting is:  What, if anything, is already known on this subject?  The types of plasma are broad and varried.  Any help to narrow the field of my experiments would be much appreciated.

Well, I answered my own question.  Aviation headsets can't work with ham radios.  Microphone impedance is incompatible.  Its possible to replace the headset's microphone with one of lower impedance, then jumper-wire the connectors to get to the radio, but the broadcast noise supression qualities of the original headset microphone are lost.  Aviation headsets are more comfortable to wear for long periods and are generally better at blocking ambient noise for the operator, but its not enough to make me willing to gut my expensive David Clarks.

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