Frank,

My e-mail address is above. Thank you for all your help. I will try this.

Dan

Frank wrote:
Frank,

Thank you. Is there any way you can forward the saved parameters. This is
a screwdriver antenna, I will remeasure the coil and double check.

My modeling of the free space antenna showed about 4 Ohms but it was with
a much simpler program. It was that program I used to measure Q.

Thanks,
Dan


Hi Dan,

I have run the program to determine the precise resonance. The parameters
are as follows: Inductor 89.3 uH, and resonant at 3.92 MHz. I can send you
a zipped NEC output text file. It is about 190 kB. Also the NEC code I
used. You can plug in the appropriate data into an Excel spread sheet. If
you need any specific graphical output I can it as a JPEG file. I used the
default input source of 1 V peak, which accounts for the low power values in
the output file. The E-field data is far field, normalized to 1 meter.

The inductor is described as a lumped element, complex impedance, of 4.9 +
j2200 ohms. I arrived at this value based on your Q of 450, and just played
around with the imaginary value to achieve resonance within the 75 meter
band.

Let me know if I can send the above information to the address shown in your
posting.

Regards,

Frank