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gareth October 12th 15 05:00 PM

Superposition
 
The forward and reflected waves in transmission lines and antennae do not
affect each other by the principle of superposition (although they act
together to
give an apparent (and only apparent) standing wave.

Why, then, should a transducer connected to one end of a transmisison line
(such
as the PA stage of a TX) be affected by the apparent VSWR, as we know that
it is,
but why does not the principle of superposition apply in this case?

Just curious.

(The enquiring mind - the mark of the _REAL_ Radio Ham)



Stephen Thomas Cole[_3_] October 12th 15 06:17 PM

Superposition
 
"gareth" wrote:
The forward and reflected waves in transmission lines and antennae do not
affect each other by the principle of superposition (although they act
together to
give an apparent (and only apparent) standing wave.

Why, then, should a transducer connected to one end of a transmisison line
(such
as the PA stage of a TX) be affected by the apparent VSWR, as we know that
it is,
but why does not the principle of superposition apply in this case?

Just curious.

(The enquiring mind - the mark of the _REAL_ Radio Ham)


I'm pleased to see that you've started drinking a little later in the day,
Gareth. That's progress, at least.

--
STC // M0TEY // twitter.com/ukradioamateur

joe October 12th 15 10:45 PM

Superposition
 
gareth wrote:

The forward and reflected waves in transmission lines and antennae do not
affect each other by the principle of superposition (although they act
together to
give an apparent (and only apparent) standing wave.

Why, then, should a transducer connected to one end of a transmisison line
(such
as the PA stage of a TX) be affected by the apparent VSWR, as we know that
it is,
but why does not the principle of superposition apply in this case?


You have energy travelling toward the PA (the eflected wave. It has to be
dissipated. That adds heat to the PA.



Just curious.

(The enquiring mind - the mark of the _REAL_ Radio Ham)


You really should try to use google and look things up that interest you
rather than try to initiate discussions for the sake of discussing
something.


rickman October 13th 15 02:07 AM

Superposition
 
On 10/12/2015 5:45 PM, joe wrote:
gareth wrote:

The forward and reflected waves in transmission lines and antennae do not
affect each other by the principle of superposition (although they act
together to
give an apparent (and only apparent) standing wave.

Why, then, should a transducer connected to one end of a transmisison line
(such
as the PA stage of a TX) be affected by the apparent VSWR, as we know that
it is,
but why does not the principle of superposition apply in this case?


You have energy travelling toward the PA (the eflected wave. It has to be
dissipated. That adds heat to the PA.



Just curious.

(The enquiring mind - the mark of the _REAL_ Radio Ham)


You really should try to use google and look things up that interest you
rather than try to initiate discussions for the sake of discussing
something.


There are times when I wouldn't mind trying to discuss things with him.
But the idiots in this and other groups just jump on his **** so bad
it is ridiculous. Then he gets wound around the axle making it
impossible to discuss anything.

--

Rick

John S October 13th 15 05:04 AM

Superposition
 
On 10/12/2015 4:45 PM, joe wrote:
gareth wrote:

The forward and reflected waves in transmission lines and antennae do not
affect each other by the principle of superposition (although they act
together to
give an apparent (and only apparent) standing wave.



Please allow me the liberty of rephrasing your sentence as follows:

The forward and reflected waves in transmission lines and antennae do
not affect each other. However, by the principle of superposition they
act together to produce a standing wave.

(Superposition is the adding together of two or more stimuli to produce
one response.)


Why, then, should a transducer connected to one end of a transmisison line
(such
as the PA stage of a TX) be affected by the apparent VSWR, as we know that
it is,
but why does not the principle of superposition apply in this case?


You have energy travelling toward the PA (the eflected wave. It has to be
dissipated. That adds heat to the PA.



No, it does not have to be dissipated. Most of it is reflected back
toward the antenna by the transmitter's output network. There may be
some dissipation at the transmitter, but that is due to losses in the
network.




Just curious.

(The enquiring mind - the mark of the _REAL_ Radio Ham)


You really should try to use google and look things up that interest you
rather than try to initiate discussions for the sake of discussing
something.


You really should learn to understand and use the Smith chart. I know,
it has a bit of a learning curve associated with it for the uninitiated,
but you could greatly benefit from studying it.



gareth October 13th 15 10:46 AM

Superposition
 
"rickman" wrote in message
...

There are times when I wouldn't mind trying to discuss things with him.
But the idiots in this and other groups just jump on his **** so bad it is
ridiculous. Then he gets wound around the axle making it impossible to
discuss anything.


I do not originate, "****", as you so crudely pit it.

Shame on you for that.

I do not know what you mean by, "wound around theaxle", but I will continue
to try
to maintainn the gentlemanly public face of amateur radio in the face of
gratuitous
and infantile sneers, such as are quoted above.

Now, back to the OP, perhaps?




Mum October 13th 15 01:43 PM

Superposition
 
On Tue, 13 Oct 2015 10:46:35 +0100, gareth wrote:



I do not originate, "****", as you so crudely pit it.



A nice big spoonful of castor oil will soon clear your tubes out, dear.


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