QRZ Forums - Antennas, Feedlines, Towers & Rotors for Tuesday 21 February 2017
 

Antennas, Feedlines, Towers & Rotors

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3-element 20m wire Yagi on PVC suggestions

Posted: 21 Feb 2017 01:50 AM PST
http://forums.qrz.com/index.php?thre...stions.556157/

Moxon is down, due to very heavy winds (actually, the 40mm aluminum part of
the mast could not handle the wind load). This isnt bad, as I was planning
to take it down this week, anyway. The antenna itself is barely damaged.
It sort of folded over, and the guying held it on the roof.







Time to graduate to a quck-and-dirty 3-element antenna.





Ive been looking through various antenna books, but am not very good at
understanding/reading the charts per spacing between elements, and what...



3-element 20m wire Yagi on PVC suggestions

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Common mode currents. So what?

Posted: 20 Feb 2017 11:16 PM PST
http://forums.qrz.com/index.php?thre...o-what.554238/

Gday all, just thinking out loud in a sense regarding baluns and such. Yes
Ive built both voltage and choke baluns with good results and they all work
fine. However if ones antennas are basically well engineered and built I
see no real advantage in using a balun with heaps of common mode current
rejection.



Not with a properly balanced dipole/inverted V or full wave loop anyway!
For an inherently unbalanced antenna structure like an OCF dipole....well
yes, but not ordinarily. I...



Common mode currents. So what?

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My homebrew QRO remote controlled balanced line tuner...

Posted: 20 Feb 2017 10:37 PM PST
http://forums.qrz.com/index.php?thre...-tuner.556140/

Here is my homebrew QRO balanced line remote controlled tuner powered by
Google! I have named it the "rsTuner, powered by Google". It is a
Raspberry Pi, Stepper motor Tuner - remote controlled.









This tuner is completely remote controlled by my pc and or Android phone on
my home Wifi network.



A Raspberry Pi 3 with Wifi is housed inside the tuner along with an Arduino
Uno board and CNC shield which has driver boards for the stepper motors.
24v power is...



My homebrew QRO remote controlled balanced line tuner...

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New Ham needs antenna plan.

Posted: 20 Feb 2017 08:44 PM PST
http://forums.qrz.com/index.php?thre...a-plan.554581/

As the title implies, Im fresh meat So fresh, in fact, I dont even take
the exams until the end of the month, and am currently grinding my way
through the General book. Im also a guy who needs to apply skills to
actually learn them, so Im trying to kill two birds with one stone and
develop an antenna plan for the QTH.



Right now my primary HF interests are local/regional phone and maybe some
data work. Seeing how Im starting on the bad side of the solar cycle, Im
focusing on the 40m...



New Ham needs antenna plan.

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Inverted L Using DX Engineering 43' Vertical

Posted: 20 Feb 2017 08:38 PM PST
http://forums.qrz.com/index.php?thre...rtical.555398/

Hi guys, I was wondering if I could use my 43 DX engineering vertical along
with an inverted L from Ni4L antennas for my 160 mtr inverted L? I dont
really use the vertical and I was wondering if I could simply zip tie the
wire antenna to the 43 vertical and pull the wire from it over to my tower
to complete the inverted L. I already have the ground radials under the
vertical so it would be the perfect place to do this. I called Ni4L and he
was unsure if the vertical would cause performance...



Inverted L Using DX Engineering 43 Vertical

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RG8X Return Loss Spec

Posted: 20 Feb 2017 02:19 PM PST
http://forums.qrz.com/index.php?thre...s-spec.556163/

Does anyone have any idea what the return loss of a 50 ohm terminated 100
ft length of RG8X should look like over the HF range? Im trying to come up
with a minimum RL number I can use to test out cables I already have in
conduits. I cant find any manufacturer specs on this. Anyone know why its
not specified? What I have found on some coax brands is an impedance
tolerance spec, typically +/- 2 ohms. This would work out to an SWR of
1.04:1 if everything else was perfect. Whats reality?

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EFHW antenna analysis

Posted: 20 Feb 2017 10:04 AM PST
http://forums.qrz.com/index.php?thre...alysis.556138/

Please find an interesting analysis of EFHW antenna by KX4O at Hamradio.me



http://www.hamradio.me/antennas/of-f...eedpoints.html



http://www.hamradio.me/antennas/disp...-currents.html



73 Danny E73M



P.S. I expect the Dave, KD6RF to post the reply to this with his usual
harassment, libel and defamation post containing references not related to
this topic.

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Alinco EDX-2 remote tuner: Max power while tuning?

Posted: 20 Feb 2017 07:24 AM PST
http://forums.qrz.com/index.php?thre...tuning.556142/

I would like to use an Alinco EDX-2 remote tuner with a non-Alinco radio.



What is the min/max power level that the exciter should output during the
tuning cycle?







Mike, WA7ARK

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EZNEC Radial field modelling

Posted: 20 Feb 2017 04:48 AM PST
http://forums.qrz.com/index.php?thre...elling.554671/

Hi,

I have a garden with space 25M x 5 M.

I want to model a 1/4 wave vertical on that radial field (WITH 120
radials) using EZNEC just t see if its worth the effort.

Is there an easy way or tool to set up the radials without working out each
end point using trig?

I see it can be done easily for a circular radial field but I dont know for
a rectangular one.

Iain G4SGX