Understanding Parallel to Series conversion
Richard Clark wrote:
On Sat, 15 Jan 2011 07:50:13 -0600, joe wrote:
joe wrote:
Saving a few cents on Lits wire will cost you almost half of the power
you could deliver to the tank.
This won't give you maximum power transfer.
Correction: You'll lose much more than half the power.
Hi Joe,
Care to go deeper? Would that "more than half the power" be 3.1dB?
6dB? 20dB?
Why "half the power" as a round number instead of a tenth?
73's
Richard Clark, KB7QHC
Why, because I chose not to go into detail.
If you look only at a resistive source impedance, the most power we can
get is
((Vsource/2)**2)/Rsource
Now the example starts with Rsource = 58 ohms and is trying to transform
that to match a 1.5 Meg load. The power available from a source with 1.5
M source impedance is much less than that from a 58 ohm source.
Hint : 58/1.5M
So, doing something to match the tank to the load could be much more
effective. A tapped coil or additional winding has been suggested.
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