On Fri, 14 Jan 2011 19:35:43 +0100, "Antonio Vernucci"
wrote:
Well, it's not mine and it appears in you post as 54 pF. Isn't 58R in series
with 54 pF equal to 58-2947j? And isn't the parallel equivalent of that equal
to 149k ohms of resistance in parallel with -2948 ohms of reactance (~54 pF)?
I'm pointing out that you slipped a decimal point or you would have seen that
54 pF is too much it results in the parallel equivalent resistance of 149k
rather than 1.49M. Mike's figure of about 18 pF (17 pF series combination)
will do the job.
Yes, at one o' clock in the morning, I slipped the decimal point. So, the total
antenna series capacitance should have been about 17 pF, not 54 pF. This
requires putting a 19-pF capacitance in series with the antenna, not 85 pF.
And the inductance resonating the residual parallel capacitance becomes 1,490 uH
instead of 470 uH.
Sorry for mistake!
73
Tony I0JX
Hasn't anyone pointed out that this a problem made for using a Smith
Chart?
(Since no one really seems capable of doing the math :-)
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice
480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at
http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.