A while ago, there was a question involving subject of band switches
able to short out coil turns, so no leads remain unshorted and therefore
avoid
Tesla coil effect. Now, someone (I can't recall who was it) suggested that
it
is more likely that if you have non-shorting band switch, there is greater
possibility of arcs within Pi-L then with Pi tank circuit.
I'm not sure to follow this ( I believe it is just the opposite
situation) and
therefore I would like to hear/learn about this more.
I did some math for a plate impedance of 2000 ohms and Z load 50 ohms
for Pi and Pi-L tank (example from ARRL handbook). Since there is step-down
impedance between L1 and L2 in Pi-L, voltages across L1 and L2 must be
less than voltage across L in Pi. Inductance of L1 in Pi-L is about twice
the L in Pi - therefore less volts per turn then in L in Pi, which led me
to conclusion that non-shorting band switch combined with Pi tank is
more prone to arcs then when combined with Pi-L.
Am I wrong or not? Enlighten me please.
Sasha YZ6X
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