Jeff Liebermann wrote:


And what do you do when they don't work? Cut-n-try is a rather
expensive way to build something that works. Given infinite time and
materials, it will eventually result in a functional antenna. You
could probably do that at HF frequencies where construction errors are
about equal to calculation errors. However, don't try it at microwave
frequencies. While it's possible to cut-n-try various microwave
structures, it's messy, difficult, prone to error, and not very
effective. The techniques used to build a coat hanger ground plane at
VHF just are not going to work at X-band.


Well, ya', an adjustable whip(s) is good, especially with the cost of
copper and the pain in "resoldering your prunings." LOL

The only way to get it close to right the first time is to calculate
first, calculate again, have someone check the calculations, drink
some wine, and check your calcs again. Then build it.


You have wine? Why didn't you say so, that changes everything:

1) Put antennas away.

2) Have a glass of wine and contemplate the design/construction.

3) Repeat 2) until ALL wine is gone.

4) Take a nap.

5) Now get the antenna(s) back out and begin work ... LOL

A few times, I have just grabbed up some tubing/wire a variable
condenser or two, and "eyeballed" the construction--past experience
provided "ballpark" figures/placements/wiring, testing, trimming and
adjusting got me the final result ...

Yep. That will work at HF because the lower frequencies allow for
much larger construction errors. Your antenna lengths could be off
many cm and still work. Your xmitter can also tolerate a substantial
VSWR and still be considered functional and useful. You match box
could be grossly inefficient trying to match your constructed antenna,
and work well enough. Now, try that at microwave frequencies, where
every milliwatt is precious, where VSWR is too crude and reflection
coefficient comes close to describing the ultimate goal of a perfect
match, and where cm errors are disastrous. Some broadband antennas
(helix and horn) are very forgiving and can be build fairly crudely.
Others (stripline, phased arrays, cavity backed antennas, etc) have a
higher Q and require more accuracy than the eyeball can provide.


Or, to summarize, the more complex the antenna, the more meters you are
going to need ... LOL

Mainly, I point this out so as not to "obsfucate" that layman, or
discourage him ... the men who first started/awakened my interest in
such things never gave any indication, to me, they had an understanding
of calculus, only basic-math/algebra, and of course, geometry!

Same here. My original mentors were operators first and technical
types last. However, I saw the light (and the distinction) between
amateur and professional when I went to college and saw that radio
things were easier and better if they were calculated (and understood)
first. I have several humorous examples of hams operating in a
professional environment (engineering lab at a radio manufactory) and
failing miserably using cut-n-try methods popularized by ham radio.


Indeed, mine drank beer too! grin

Indeed, at least one passed away without ever expressing any real
interest in learning it!

There are suspicions that math may hasten one's demise. Perhaps he
tried to do a calculation before he died?


If away from my laptop, the programmable calculator is always in my
pocket! (I mean, my gawd man, I have space invaders on it!) straight-face

...

Also, I assembled a small list of tech patents that appear to be
bogus. I was going to post the list on the web but my attorney
advised against it. Even holders of bogus patents can sue for
damages. Oh well.


.... some patents are NOT what they used to be ... but then, there has
always been some suspicion about the politics involved, not to mention
courts ...

Regards,
JS

On Sep 18, 2:14*pm, John Smith wrote:
Jeff Liebermann wrote:

And what do you do when they don't work? *Cut-n-try is a rather
expensive way to build something that works. *Given infinite time and
materials, it will eventually result in a functional antenna. *You
could probably do that at HF frequencies where construction errors are
about equal to calculation errors. *However, don't try it at microwave
frequencies. *While it's possible to cut-n-try various microwave
structures, it's messy, difficult, prone to error, and not very
effective. *The techniques used to build a coat hanger ground plane at
VHF just are not going to work at X-band.

Well, ya', an adjustable whip(s) is good, especially with the cost of
copper and the pain in "resoldering your prunings." *LOL

The only way to get it close to right the first time is to calculate
first, calculate again, have someone check the calculations, drink
some wine, and check your calcs again. *Then build it.

You have wine? *Why didn't you say so, that changes everything:

1) Put antennas away.

2) Have a glass of wine and contemplate the design/construction.

3) Repeat 2) until ALL wine is gone.

4) Take a nap.

5) Now get the antenna(s) back out and begin work ... LOL



A few times, I have just grabbed up some tubing/wire a variable
condenser or two, and "eyeballed" the construction--past experience
provided "ballpark" figures/placements/wiring, testing, trimming and
adjusting got me the final result ...

Yep. *That will work at HF because the lower frequencies allow for
much larger construction errors. *Your antenna lengths could be off
many cm and still work. *Your xmitter can also tolerate a substantial
VSWR and still be considered functional and useful. *You match box
could be grossly inefficient trying to match your constructed antenna,
and work well enough. *Now, try that at microwave frequencies, where
every milliwatt is precious, where VSWR is too crude and reflection
coefficient comes close to describing the ultimate goal of a perfect
match, and where cm errors are disastrous. *Some broadband antennas
(helix and horn) are very forgiving and can be build fairly crudely.
Others (stripline, phased arrays, cavity backed antennas, etc) have a
higher Q and require more accuracy than the eyeball can provide.

Or, to summarize, the more complex the antenna, the more meters you are
going to need ... LOL

Mainly, I point this out so as not to "obsfucate" that layman, or
discourage him ... the men who first started/awakened my interest in
such things never gave any indication, to me, they had an understanding
of calculus, only basic-math/algebra, and of course, geometry!

Same here. *My original mentors were operators first and technical
types last. *However, I saw the light (and the distinction) between
amateur and professional when I went to college and saw that radio
things were easier and better if they were calculated (and understood)
first. *I have several humorous examples of hams operating in a
professional environment (engineering lab at a radio manufactory) and
failing miserably using cut-n-try methods popularized by ham radio.

Indeed, mine drank beer too! *grin

Indeed, at least one passed away without ever expressing any real
interest in learning it!

There are suspicions that math may hasten one's demise. *Perhaps he
tried to do a calculation before he died?

If away from my laptop, the programmable calculator is always in my
pocket! (I mean, my gawd man, I have space invaders on it!) *straight-face

* ...

Also, I assembled a small list of tech patents that appear to be
bogus. *I was going to post the list on the web but my attorney
advised against it. *Even holders of bogus patents can sue for
damages. *Oh well.

... some patents are NOT what they used to be ... but then, there has
always been some suspicion about the politics involved, not to mention
courts ...

Regards,
JS

JS
Mathematics is founded on the proposition of zero means nothing ONLY
if you ignore the presence of the weak force.
Thus mathematic has contaminated that which is the "equal" sign which
then is misused without the assumption of the underlying condition
You can cancell the effects of gravity but it is a lot different to
canceling the weak force.
Put scales on a bench to oppose gravity does nothing to neutralise the
weak force
Thus in mathematics you can obtain negative answers which is the
measure of the weak force which is contradictory
to the "term" nothing in celestial terms but possibly is O.K. in
polotics
The CERN project is based on the collision of particles of the same
polarity but without the constraints of sideways movement
but the electron is much smaller than the area taken by an electron so
to my mind there is no collision only contra or lamina
flow UNLESs the particles are of different polarities which some
theorise as equating to the big bang.!
Art
Have fun
Art

On Thu, 18 Sep 2008 12:14:31 -0700, John Smith
wrote:

Well, ya', an adjustable whip(s) is good, especially with the cost of
copper and the pain in "resoldering your prunings." LOL

Incidentally, one of the tricks I learned (the hard way) was to
replace the mobile whip antenna with a piece of copper electrical
wire. Then cut it to length, tune, optimize, test and whatever. Once
the optimum length is established, replace the copper wire antenna
with the real stainless whip, cut to the exact same length.

You have wine? Why didn't you say so, that changes everything:

The antenna transfer function of wine is highly exponential and very
non-linear. A little wine will produce a superior antenna. However,
incremental increases in wine dosage will tend to have lesser effects.
At some threshold, additional can cause a substantial drop in
performance. It may even go negative. Think equilibrium.

Or, to summarize, the more complex the antenna, the more meters you are
going to need ... LOL

Kinda reminds me of a former tech. All day, he would spend his time
working with the latest state of the art test equipment in the lab.
After hours, he would drag out his ham radio, and tune the xmitter to
maximum using a light bulb dummy load. Attempts to convince him that
the company test equipment might be useful for dealing with his radios
were futile.

If away from my laptop, the programmable calculator is always in my
pocket! (I mean, my gawd man, I have space invaders on it!) straight-face

That doesn't leave much room for the pocket protector. I collect HP
calculators. There are numerous calculators scattered around the
office and house. No need to drag a calculator around.

... some patents are NOT what they used to be ... but then, there has
always been some suspicion about the politics involved, not to mention
courts ...

There's plenty wrong with patents that I don't wanna get into. Suffice
to say that it's very helpful to understand something about patents
before trying to create one. I'm just suggesting that you make the
effort to read patents.

Groan. I decide to stay home today to recover from my home cooking.
Outside, PG&E (the power company) and the local tree service just
arrived. There goes my power...





--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sep 18, 4:51*pm, Jeff Liebermann wrote:
On Thu, 18 Sep 2008 12:14:31 -0700, John Smith

wrote:
Well, ya', an adjustable whip(s) is good, especially with the cost of
copper and the pain in "resoldering your prunings." *LOL

Incidentally, one of the tricks I learned (the hard way) was to
replace the mobile whip antenna with a piece of copper electrical
wire. *Then cut it to length, tune, optimize, test and whatever. *Once
the optimum length is established, replace the copper wire antenna
with the real stainless whip, cut to the exact same length.

You have wine? *Why didn't you say so, that changes everything:

The antenna transfer function of wine is highly exponential and very
non-linear. *A little wine will produce a superior antenna. *However,
incremental increases in wine dosage will tend to have lesser effects.
At some threshold, additional can cause a substantial drop in
performance. *It may even go negative. *Think equilibrium.

Or, to summarize, the more complex the antenna, the more meters you are
going to need ... LOL

Kinda reminds me of a former tech. *All day, he would spend his time
working with the latest state of the art test equipment in the lab.
After hours, he would drag out his ham radio, and tune the xmitter to
maximum using a light bulb dummy load. *Attempts to convince him that
the company test equipment might be useful for dealing with his radios
were futile.

If away from my laptop, the programmable calculator is always in my
pocket! (I mean, my gawd man, I have space invaders on it!) *straight-face

That doesn't leave much room for the pocket protector. *I collect HP
calculators. *There are numerous calculators scattered around the
office and house. *No need to drag a calculator around.

... some patents are NOT what they used to be ... but then, there has
always been some suspicion about the politics involved, not to mention
courts ...

There's plenty wrong with patents that I don't wanna get into. Suffice
to say that it's very helpful to understand something about patents
before trying to create one. *I'm just suggesting that you make the
effort to read patents.

Groan. *I decide to stay home today to recover from my home cooking.
Outside, PG&E (the power company) and the local tree service just
arrived. *There goes my power...

--
Jeff Liebermann * *
150 Felker St #D * *http://www.LearnByDestroying.com
Santa Cruz CA 95060http://802.11junk.com
Skype: JeffLiebermann * * AE6KS * *831-336-2558

Jeff we all make mistakes by over estimating ones ability
In making one of my antennas I made a last minuit change just in time
before I finished the antenna
It was some weeks before that antenna was tested on the air in
Australia
That test proved that reprocity with respect to radiation is not a
given!.
I had neutralised the weak force such that particles could arrive but
not depart!
Yes it was an error on my part but it didn't rule out the value of
experimentationj.
Has anybody got a use for such an antenna?. This error in many ways
provided
proof that the trail I followed was coirrect. This is why I have
delayed the sending of a antenna to AC6XG
as the correction took over some of my free time. But Jim understands
what happened not necessarily why.
as he does have trust and an open mind as well as my respect.
When I supplied an antenna to the U of I I gave them a sample of the
same antenna in Australia
because of their treatment towards me and comments made in advance of
getting the antenna.
Thus I gave them exactly what they expected to get based on pre
examine comments similar to those of this group
He who laughs last laughs longer and forever. Something like getting a
bunch of wire with lip stick all over it
Best regards
Art Unwin....KB9MZ.......xg

"Art Unwin" wrote in message
...
That test proved that reprocity with respect to radiation is not a
given!.
I had neutralised the weak force such that particles could arrive but
not depart!

Now that is worth a nobel prize! publish that and get it peer reviewed in a
respectable physics journal and i will personally nominate you for a nobel!