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Old May 19th 11, 03:03 PM posted to rec.radio.amateur.antenna
Wimpie[_2_] Wimpie[_2_] is offline
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First recorded activity by RadioBanter: Mar 2008
Posts: 329
Default Transmitter Output Impedance

On 19 mayo, 15:04, Cecil Moore wrote:
On May 19, 4:05*am, Wimpie wrote:

Regarding your helical; I don't have Eznec. Maybe you can use some
screenshots from it, put some comment to it and put that on website,
so we can view it.


Here it is:http://www.w5dxp.com/teaser2.JPG
--
73, Cecil, w5dxp.com


Hello Cecil,

Your circuit (lumped inductance example) with 100V input into 72uH
with 2570 Ohms load):

From lumped circuit simulation (Beige Bag PSPICE, version 4
professional):

I_source = 32mA, -35 degrees
I_load = 32mA, -35 degrees

This agrees with hand calculation, all phase with respect to input
voltage.

From simulation, but now a pi filter C=6pF, L=72u, C=6pF, load = 2570
Ohms
Simulation carried out with same PSPICE package without using
transmission line sections:

I_source = 38mA, -1.5 degrees
I_load = 38mA, -44 degrees.

Total required time for setting up the simulations and guessing the
parasitic components to simulate the actual inductor behavior: about
15 minutes.

As you can see good agreement without using any of the photons, speed
of light, momentum and other issues, just lumped circuit simulation
where some parasitics are added. Of course a can make a better match,
but this doesn't contribute to the discussion.

I hope that some followers or contributors will do the same simulation
in a lumped circuit simulator, so that we don't arrive in a discussion
that I am cheating.

Wim
PA3DJS
www.tetech.nl