What effect does a tuner have at the antenna?
 

David G. Nagel wrote:
Cecil Moore wrote:
The point is that if an amp is equipped with foldback,
it probably cannot vaporize a severely mismatched antenna
without the aid of an antenna tuner.

Actually it will most likely vaporize the tuner first...

With #10 wire in the tuner coil and #26 wire in the
hamstick coil?
--
73, Cecil http://www.w5dxp.com

What effect does a tuner have at the antenna?
 

Lumpy wrote:
You have a tuner that vaporizes hamsticks?

Assume a legal limit amp that folds back when mismatched.
Add a legal limit tuner and indeed you can vaporize
hamsticks.
--
73, Cecil http://www.w5dxp.com

What effect does a tuner have at the antenna?
 

Cecil,
I think I'll take my tuner and go home. Not saying it wasn't fun,
just other things to do, you know, that four letter word... 'X'ork.
- 'Doc

What effect does a tuner have at the antenna?
 

Cecil Moore wrote:
Lumpy wrote:
You have a tuner that vaporizes hamsticks?

Assume a legal limit amp that folds back when mismatched.
Add a legal limit tuner and indeed you can vaporize
hamsticks.

Hmmm. Past experience suggests my Russian 5KW amp has no "foldback." I
hesitate to think other experience the same--but, judging from some
signals, it is quite likely!

BUT! Very happy with the SDR!

Regards,
JS

What effect does a tuner have at the antenna?
 

On Wed, 04 Jun 2008 12:33:16 -0500, Cecil Moore
wrote:

A popular myth is developing that the tuner has no effect
at the antenna feedpoint and the only goal is to make the
transmitter "happy". My question is: if we monitored
only the forward current or forward power at the antenna
feedpoint, could we still adjust the tuner? If the answer
is "yes", the myth is false.

Would it help to attach an antenna analyzer to the back side of a
tuner, tune the antenna and see if it affects the analyzer?
--
73 for now
Buck, N4PGW

www.lumpuckeroo.com

"Small - broadband - efficient: pick any two."

What effect does a tuner have at the antenna?
 

Buck wrote:
Would it help to attach an antenna analyzer to the back side of a
tuner, tune the antenna and see if it affects the analyzer?

Certainly it changes the impedance looking into the tuner
input and that has an effect on the entire antenna system.
The forward and reflected voltages, currents, and powers are
at their maximum values when the tuner achieves a Z0-match.
--
73, Cecil http://www.w5dxp.com

What effect does a tuner have at the antenna?
 

Cecil Moore wrote:
Michael Coslo wrote:
It's a short drive from there to "the tuner has no effect on the
antenna".

Actually, it went farther than that:

From QRZ.com regarding tuners:

"The tuner has absolutely no effect at the antenna."

From eHam.net regarding tuners:

"Does nothing. The tuner as the other poster said,
just makes your radio happy."

So we have a score or more posts that boil down to "at" or "on", when it
is blatantly obvious what the intent of the statements were.

....good job!

What effect does a tuner have at the antenna?
 

Jim Higgins wrote:
On Wed, 04 Jun 2008 12:33:16 -0500, Cecil Moore
wrote:

A popular myth is developing that the tuner has no effect
at the antenna feedpoint and the only goal is to make the
transmitter "happy". My question is: if we monitored
only the forward current or forward power at the antenna
feedpoint, could we still adjust the tuner? If the answer
is "yes", the myth is false.


I suspect many hams are confused on this subject and that many more
just express themselves awkwardly.

What's totally beyond my understanding is why so many here repeatedly
waste their time helping you have fun with either category.

Bravo! Endless self-indulgent mental masturbation appears to be the
function of far too many posts over the last several years. This has
virtually ruined what at one time was a fine resource for amateurs
interested in antennas. I used to recommend that people who had
questions about or interest in antennas come to this newsgroup. I
stopped doing it, and now only take a look myself every week or two to
see if anything has changed...it only seems to get worse.

It's a damn shame what a few frequent posters have done to this newsgroup.

What effect does a tuner have at the antenna?
 

Cecil, W5DXP wrote:
"If we monitored only forward current or forward power at the antenna
feedpoint, could we still adjust the tuner?"

Yes because a conjugate match delivers all available power (a maximum)
and a conjugate match also exists at every pair of terminals between the
transmitter and the antenna if the tuner and line are essentially
lossless.

Best regards, Richard Harrison, KB5WZI

What effect does a tuner have at the antenna?
 

Richard Harrison wrote:
Cecil, W5DXP wrote:
"If we monitored only forward current or forward power at the antenna
feedpoint, could we still adjust the tuner?"

Yes because a conjugate match delivers all available power (a maximum)
and a conjugate match also exists at every pair of terminals between the
transmitter and the antenna if the tuner and line are essentially
lossless.

I made an interesting assertion on a related thread over
on QRZ Q&A.

"A CONJUGATE MATCH TO A MISMATCHED LOAD GUARANTEES MAXIMUM
POWER REFLECTED FROM THE LOAD!"

The maximum available power is delivered to a mismatched load
when a conjugate match exists. It follows that is also the
point where the incident power is maximum and the mismatched
load will be reflecting the maximum amount of incident power.

Apparently, one could adjust an antenna tuner for a conjugate
match by monitoring the reflected power at the *output* of the
tuner and adjusting for a maximum. :-)
--
73, Cecil http://www.w5dxp.com