->Consider that if these reflections are hapenning at the speed of light
>(small multiples of).
Nope! Always the speed of light in the coax or twin lead reduced by
the velocity factor of the particular line, typically, 60 to 80% of
llight speed.
>The echo or delay will be unnoticeable on SSB or CW
>especially when dealing with atmospheric conditions that will certainly
>introduce more noticable distortions.
Of course not, the echos on the transmission line are in microseconds,
millionsth of one second. Absolutely NOTHING in an HF amateurs
radio can respond to microsecond time duration signals, in particular
your headphones, speaker, printer, etc., etc.!! Atmospherics are
large fractions of a second, or seconds in duration.
>Fast scan Television is another story because the modulation technique is
>highly sensitive to distortions of the phase relationships. Ghosting
>results.
Yes, when the Fast Scan is up at UHF and microwave frequencies,
a-la commercial television! But meaningless at HF SSTV applications!
>For SSB & CW, the distorted waveshape that results from reflections will
>still energize the antenna and produce the electromagnetic fields.
So what??! Is there anyone on the planet who can hear it?? Of course
not. Does it matter to the transmitter, the rcvr, the universe? If you
think so, please explain.
Reflections, microseconds, 2 or 3 at most, at "dit" at 30 wpm, 43,000
microseconds. Can you hear a dit at 30 wpm; think you could hear
the microsecond bounce??
>So the questions remaining are; how much more loss is incurred in all that
>makes up the transmission line including tuner, balun and connectors
> and how much power is the transmitter able to make?
I have absolutely no idea what this double talk, nonsense statement
is trying to say! Do you have any idea what you are trying to say,
or ask?
>These are valid points because if the transmitter is unable to make
>full power, it won't be there to lose.
If the transmitter sees the correct impedance, resistance and
reactance, it will develop full power. An antenna tuner,
transmatch, line impedance matcher, wharever you
choose to call it, will insure the transmitter WILL develop
full power, and it will go to the antenna and be radiated!!
Absolutely!
> And even though out of phase relationships of the incident to reflected
>waves can't cancel out the power, they will cause higher peak values of
>both voltage and current that can increase losses.
Yes, that is what we call vswr, and the losses are well known--
tiny!
Jim, for heavens sake, quit trying to restate in non-correct words
what you have been told now for days!! If you understand what you
have been told, you now can determine EXACTLY what your
suffered losses will be, OK? Incredibly low, and meaningless!!
Do you want to know why the Big Guns design for low vswr??
It is to save the time they would lose in a contest situation to
adjust the tuner when doing rapid QSY -- that is the reason!
And they do a lot to keep a low vswr over a small percentage
of a particular CW segment, or SSB segment of the band;
certainly not the entire given band. Why, to save the time
otherwise spent adjusting the antenna impedance matching
device in the rig to antenna transmission system.
If you really need it, I have a video, actually a video copy of a movie
that was produced at Bell Telephone Laboratories decades ago
that explains standing waves, power transport and all about
transmission lines. However, if you would take the time to
read the ARRL Radio Amateur's Handbook or better, the
ARRL Antenna Book, in particular the chapters on connecting
the transmitter to the antenna and the stuff about about
transmission lines and tuners, you would LEARN a bunch!
The BTL video uses a mechanical device, dashpots, and
even line impedance matchers in a amazingly beautiful
demonstration of all this.
73, Jim, KH7M
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