antenna theory made easy
On Sunday, January 26, 2014 10:21:01 PM UTC-6, Jerry Stuckle wrote:
And yes, the title is about antennas. But you're replying to messages
about verticals.
Nope, please learn to read. Here's your posting to which I replied:
So? Even at 50 ohms, 1KW is a lot of voltage.
There's no mention of vertical antennas - just a broad sweeping assertion that "1KW (sic) is a lot of voltage". BTW, is that potassium watts, Kelvin watts, or the kinetic energy in 1kW? Hint: 'K' is not the correct prefix for kilo.
Now back to the subject of my original posting: IMHO, 1kW into 50 ohms is not a lot of voltage since I have more voltage than that in my house. FYI, 50 ohms is considered to be one of the lower resistances which ohm's law says results in a lower voltage that if it were a higher resistance.
If 1kW is a "lot of voltage" at 50 ohms, how low must the resistance go for it not to be a "lot of voltage"?
A resonant 1/4WL monopole with a good ground plane has a resonant feedpoint impedance around 35 ohms which at 1kW results in only 187 volts at the feedpoint. How anyone could consider 187 volts to be "a lot of voltage" stretches the imagination.
If you really want to talk about "a lot of voltage", talk about the voltage that exists at the tip top of that 35 ohm 1/4WL monopole when only 187 volts is being applied at the base feedpoint. I get more than 10,000 volts. Now that's indeed a lot of voltage.
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73, Cecil, w5dxp.com
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