"Old Ed" asked -

What parameters does a user input into your newly-posted program
in order to estimate tuner and/or balun losses?

=========================================
Ed,

Program LINELEN's primary purpose is to calculate the impedance
presented to a tuner. It will assist the user to change the length of
the transmission line, hopefully to bring the impedance into a range
of values which can be better handled by a tuner.

The program cannot predict tuner losses. It has not been designed to
so.

You are asking what input data would be required if I wrote another
program which included calculation of losses in a tuner.

There is already a program named T_TUNER which designs a common or
garden T-tuner and also estimates its losses. In practice, nearly
every manufacturer uses the same basic circuit which consists of two
variable capacitors, each of about 350 pF maximum, 30 pF minimum, and
a coil which may be tapped to change bands or it may be a variable
roller-coaster.

For a different tuner circuit another program is needed. There are
L_TUNER, Pi_L_NET, PI_TANK. And DIPOLE3 which deals with antenna +
balanced line + balun + coax + Tuner Design.

Download program T_TUNER and read the informative introductory notes.

Input data includes maximum capacitor settings. The program
automatically prevents maximum capacitor settings from being exceeded.
This is a form of technical information which restricts practical
operation. Minimum component settings are not called for. But the
program user must keep in mind, when calculated capacitor settings are
less than the actual value with capacitor vanes completely unmeshed,
the tuner won't work.

The program asks for capacitor Q and coil Q. The progam user will have
to take the tuner out of its case and inspect construction and then
make use of his experience and judgement. It will not be worthwhile
taking the thing apart to measure component Q. Q is needed to estimate
component losses for a given transmitter power. The program gives
advice about estimation of Q values.

When a program includes design of a coil, length, diameter, wire
gauge, etc., its Q is always calculated. Whether the power loss is
calculated depends on program application.

The program user will also have to estimate maximum working volts of
the capacitors although this is not a program input. But the program
does calculate and display actual capacitor volts for a given
transmitter power.

Equipment power related performance parameters are nearly always
estimates. T_TUNER has built-in estimates. There is no point in
calculating to a greater accuracy than contained in the user's input
data. Very often crude estimates are good enough. As the programmer
I reserve the right to decide just how crude. And you can't argue with
me. You can always have your money back. ;o)

The same applies, for example, to estimates of radiated RF power for a
given transmitter output power when there are losses in the SWR
meter, the tuner, the balun, transmission line, antenna, and the
ground.

It is only necessary for a program user to realise that he, himself,
invariably makes estimates.

Most amateurs and many professional enginers suffer from delusions of
accuracy, often proudly naming their measuring instruments.
----
Reg, G4FGQ.