It was easy to predict the SWR/impedance discussion did wrap on itself with
marginal progress on the didactical aspect but it was very interesting
anyway.
Now, in order to resume, can I make some practical questions the scientists
can surely answer (shortly) ?
1) An ideal 50 Ohm SWR meter, with no line lenght, is placed directly
between a 100 Ohm pure resisistive load and a 50 Ohm source. What does the
meter read ? Are there standing waves between source and load ?
How much power is on the load ? Where is the lost power gone ?
2) The generator frequency is X and a quarter wave line of 70.71067812 Ohm
is placed between its output and the load. Is it the effective matcher loss
equal to the typical line loss at frequency X or is it different ? Why ?
What's the power on the load this time ?
3) A quarter wave shorted stub is made of the same line and connected to the
generator output of the previous
example, what does it happen with impedances, losses and SWR ? What is the
VSWR on the short end of the stub ? And at 1/8 wavelenght from the short ?
What power is dissipated by the shorted stub ?
4) The source is 50 Ohm resistive, the load is 100 Ohm resistive, the
generator frequency is X. Two quarter wawe lines of 70.71067812 Ohm are
connected back to back with a nominal 50 Ohm SWR/impedance analyzer in the
connection point between the lines.What does the analyzer reads in term of
SWR and impedances (in the form of real and imaginary part) ? What would it
read on the source side ? And on the load side ?
Thank You.
73,
Mauri I4JMY (one of IR4T)
E-mail: i4jmy@iol.it
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