[nrv-hams] RF feedback was :Thanks to Carter for Help with PL-259 Connectors

[Ron Angert]

Don,
Congratulations on getting on the air an making a contact!

What you are seeing is often a symptom of what we call 'RF Feedback' and
you can read all about it at the links below, but the executive summary is
to look at RF grounding of all your station components (power supply,
transceiver, tuner, etc) and make sure that all the coax is of commercial
quality (nothing that says Radio Shack), all connectors installed (soldered
or crimped) correctly, and the you have good power grounds as well.

After you do all this you can get rid of the touch sensor lights as they
generate a lot of RF noise you will run into on your receiver ;).

http://www.arrl.org/grounding

http://kc.flexradio.com/KnowledgebaseArticle50426.aspx

http://www.w7aia.org/techinfo_files/docs/RCC_Mar_2007_N7ZXP_Amateur_Radio_Station_Grounding.pdf

I did not read every word of these articles, but I think they will let you
know what steps to take to get it right.

While I am sure there will be disagreement on this, I have experienced, and
theory reinforces, that the G5RV antenna is more prone to exhibit these
problems when proper grounding techniques are ignored.  This antenna is not
really resonant on every (any) frequency and works somewhat as a compromise
- but as you will see it does convert RF energy from wire into the air, so
whatever it does will get you contacts.  You also talked in an earlier post
about waiting for a balun.  Have you installed that yet?  You also talked
about the junction of the coax and ladderline being near or on the ground.
I think that needs to be raised, even if by taking the feedline away from
the horizontal part of the antenna at some angle.

I never used a balun on a G5RV, just connected the coax to the ladderline
as G5RV himself did, but that was before the ham radio world fell in love
with this device.  In any case, it should be a 1:1 not a 4:1 balun, though
that makes no sense as we are going from 50 ohms to 450 ohms (9:1), the
ladderline really is acting as a matching network, not really just a
feedline.

Ron N4AJT

Date: Sat, 08 Jun 2013 07:09:57 -0400
From: "Don Cunningham" <cunningham.don at verizon.net>
To: <NRV-Hams at mailman.qth.net>
Subject: [nrv-hams] Thanks to Carter for Help with PL-259 Connectors
Message-ID: <000001ce6438$b6e10730$
24a31590$@verizon.net>
Content-Type: text/plain;       charset="us-ascii"

I want to thank Carter for fixing my PL-259 connectors. I called him about
4:30 p.m. and he was at my house within an hour to solder two PL-259
connectors to my antenna coax. He also pointed out my temporary loop at the
bottom of the ladder line (to keep the connection off the ground) was
apparently making it difficult to tune the G5RV antenna.



I was able to monitor several nets on 80, 40, 20, 15, and 10 meters. One was
from Germany and another was from Croatia. Lots of Spanish conversations and
at least one in Arabic. I did make one DX with a HAM in Riverside, CA, on 20
meters.



New problem: Whenever I transmit, the touch-sensitive lamps in our bedroom
turn on. I guess that I will need to purchase new lamps with switches for
our bedroom to prevent further complaints from my wife.


Ron Angert in Beautiful Southwest Virginia
http://oldbikerider.blogspot.com/

"Life is a spiritual journey, whether you believe it or not, and whether
you are 'spiritual' or not." -- Tina