On 25 Sep 2006 16:32:49 -0700, "Telstar Electronics"
wrote in
m:

I have to agree that 50 ohm striplines are useless in an amp like this, it
is only important that the output impedance of the driver stages match the
driven stage.

Matching is always important for maximum power transfer.


For starters, a transmission line behaves like a transmission line
because of reactance. When your transmission line is a small fraction
of the wavelength (as is the case with your "stripline") then the
reactive impedances are insignificant. IOW, your "stripline" doesn't
behave like a transmission line (i.e, have a characteristic impedance)
because it's just too damn small.

What IS significant is the TOTAL impedance. Increasing the size of
your "stripline" will reduce the resistance while having a negligible
effect on the reactive impedance, thereby reducing total impedance. It
would also reduce resistive heating -and- increase heat dissipation;
doubling the width of your trace makes it capable of handling FOUR
times the load before it cooks off the board.


Now what were you saying about "maximum power transfer"?