Additional question;
with respect to the BOG/Beverage backlobe upwards angle, does the
test-generator antenna need to be lifted from local groundlevel by say 2-
10m?
Or can this test be done just as reliable on groundlevel?
73
Mark, PA5MW
-----Original Message-----
From: Topband <topband-bounces@contesting.com> On Behalf Of F Z_Bruce
Sent: Tuesday, October 09, 2018 3:01 PM
To: ash.kf5eyy@gmail.com; Topband <topband@contesting.com>
Subject: Topband: Beverage F/B using oscillator
Good information.
Finding the best BOG F/B.
I use an model MFJ-5014 white noise generator off the 'back' of the BOG
antenna. Then tune the receiver to find the 'minimum noise' signal
frequency. Adjust the BOG antenna length to bring it into 160 meters..
Care must be taken not to create a neighborhood noise problem.
73
Bruce-k1fz
On Tue, 9 Oct 2018 09:07:42 +0100, Ashraf Chaabane wrote:
Hi All,
I used a 1.843 oscillator to check NA beverage F/B. The mesurements were
taken 160m away from each end of the antenna. Noise level was constant. I
had 4 dB difference between front and back signals.
Is that what I should expect? Is 1 wavelength distance enough to do this
experience?
This will be repeated with different terminations and I want to make sure
I'm doing it correctly. It will also be applied on the newly installed BOG
to determine optimum length.
Tnx and see you on the air!
--
Ash ~ 3V8SF
Topband: *http://www.kf5eyy.info/topband.htm
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