Thread: 4NEC2?
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Old October 15th 18, 01:16 PM posted to uk.radio.amateur,rec.radio.amateur.antenna
Spike[_3_] Spike[_3_] is offline
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Default 4NEC2?

On 15/10/2018 01:20, Jeff Liebermann wrote:
On Sun, 14 Oct 2018 11:12:14 -0700, Jeff Liebermann
wrote:


Since you prefer a minimalist approach to test equipment, as an
alternative to your light bulb, may I suggest a return loss bridge:
https://www.google.com/search?q=return+loss+bridge&tbm=isch
Note that there are several basic designs and configurations but all
are fairly simple and easy to construct. Note that these are NOT the
same as directional couplers.


To use it, you need a minimum of an RF signal generator and a
voltmeter or oscilloscope. I prefer to sweep the frequency range of
interest, so I use an RF sweep generator, and display the result on an
oscilloscope. With this arrangement, you can tune your antenna
without requiring a light bulb.


So, let me get this right. By employing a return-loss bridge, an RF
signal generator, and either a voltmeter or an oscilloscope, you can get
results that a distant station can't distinguish from those obtained by
using a torch bulb?

Given your ability to estimate the performance of an antenna by looking
at it rather than employ modelling methods, I would have though you
would be sympathetic to the merits of the torch bulb approach.


--
Spike

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