[K3CAL] [CALV-AUXCOMM] Monday night net

Shawn Donley n3ae at comcast.net
Mon Jul 6 14:47:26 EDT 2020


Jim,

The 2M repeater is working at Mt Hope but currently without the ARCOM controller, just the built-in controller in the DR-1X. And yes, the RF environment at Mt Hope is problematic. Measured high noise floor and occasional very large noise floor increases around 2M from sources yet to be identified, but likely intermod products between two or more other emitters on the tower.

OK....here comes a long winded response to your question on antenna wire.

Regarding best wire for antennas, seems there are varying opinions. I think a lot depends upon what forces the wire is dealing with. For pure tensile strength, Copperweld (copper-plated steel) is the strongest. But hard to find good wire that has a thicker copper coating.  A lot of the stuff I've seen has very little copper.  Plus it's a pain the neck to work with. Kinda like a spring that wants to roll itself back up and kink. A nick in the copper and the steel gets exposed, rusts and down comes the antenna. The other consideration is bending fatigue. If the antenna wire is going to bend frequently due to the wind or a tree branch pushing into it in the wind, metal fatigue can eventually break the wire. I had this happen a few months ago to 7 strand hard drawn copper at a center insulator. It was one of those ladder-lock insulators for window line and in winds the insulator and the ladder line would flutter a bit. Eventually broke one wire a few inches off the center insulator. Not sure there's any perfect wire. Some recent discussion at TowerTalk on the subject.

http://lists.contesting.com/archives//html/Towertalk/2020-06/msg00215.html


At another QTH I once used a 130 ft long wire from the house roof peak to a mast on the detached garage.  Used a L-network tuner that was mounted in the attic and controlled by motors.  It worked pretty well, but long wire end fed antennas are very unbalanced so everything metallic in the vicinity becomes part of the antenna.  Sometimes this can cause problems with RFI.

Seems over the last few years there have been a lot of new end-fed antenna products that use a 9:1 unun at the feed point to tame the high impedance.  One example are the end feds at https://myantennas.com/wp/product-category/antennas/ that were reviewed in the March 2016 QST.   But I bet you can build one for a lot less than what these guys want.  The March 2019 QST has an article on building a 9:1 unun using available parts.

And then there's a somewhat different solution in the attached old QST article.  Maybe it also brings earthworms to the surface for fishing.

Shawn






>     On 07/06/2020 12:44 PM James Tetlow < k3uga at comcast.net mailto:k3uga at comcast.net > wrote:
> 
> 
>     Is the 2 meter repeater working normal for Mt. Hope or is there lots of noise up there?
>     I did have to put on tone squelch on my receiver due to PA vhf traffic very high.
> 
>     Another question If anyone tried it, I was thinking of using 22 strand #8 awg (not the normal 7 strand ) because it is more flexible and may not be as breakable from tree to tree with fixed on on tree and milk jug weight with pulley on the other tree. Thinking center fed, like some antennas yo can purchase, but heavy duty.
>     Was also thinking of end fed random length with outside tuner and grounded in place with ground rod, no radials this would have to slope say 40-45deg and might get 65/66ft length.
>     Thanks.
> 
>     Sent from my iPad,
>     Best Regards,
>     Jim Tetlow
> 
> 
>         > >         On Jul 6, 2020, at 10:32, W. Hackett < n3xmz.md at gmail.com mailto:n3xmz.md at gmail.com > wrote:
> > 
> >         Morning folks,
> > 
> > 
> >         We will be hosting a Zoom Meeting to coincide with Monday night Net @ 7:30
> >         pm
> >         Check in either one or the other or both. Just make sure to turn your
> >         speakers down when you check in the net via radio to eliminate FeedBack.
> > 
> >         As usual open to all hams on the radio and non hams via zoom...
> > 
> >         Click the blue link Below to sail away...
> > 
> >         Bill H
> >         President CARA Inc.
> > 
> > 
> >         Bill N3XMZ is inviting you to a scheduled Zoom meeting.
> > 
> >         Topic: CARA Inc Monday night net
> >         Time: Jul 6, 2020 07:30 PM Eastern Time (US and Canada)
> > 
> >         Join Zoom Meeting
> >         https://us02web.zoom.us/j/82550084199?pwd=MjI1WjlleEFZeFMvTjdvUStJWm9Wdz09
> > 
> >         Meeting ID: 825 5008 4199
> >         Password: 020301
> >         One tap mobile
> >         +13017158592,,82550084199#,,,,0#,,020301# US (Germantown)
> >         +19292056099,,82550084199#,,,,0#,,020301# US (New York)
> > 
> >         Dial by your location
> >         +1 301 715 8592 US (Germantown)
> >         +1 929 205 6099 US (New York)
> >         +1 312 626 6799 US (Chicago)
> >         +1 253 215 8782 US (Tacoma)
> >         +1 346 248 7799 US (Houston)
> >         +1 669 900 6833 US (San Jose)
> >         Meeting ID: 825 5008 4199
> >         Password: 020301
> >         Find your local number: https://us02web.zoom.us/u/kk2vSRo5B
> >         ______________________________________________________________
> >         Visit us on the web: https://ares.k3cal.org
> > 
> >         CALV-ARES mailing list
> >         Home: http://mailman.qth.net/mailman/listinfo/calv-ares
> >         Help: http://mailman.qth.net/mmfaq.htm
> >         Post: mailto: CALV-ARES at mailman.qth.net mailto:CALV-ARES at mailman.qth.net
> > 
> >         This list hosted by: http://www.qsl.net
> >         Please help support this email list: http://www.qsl.net/donate.html
> > 
> >     > 
>     ______________________________________________________________
>     K3CAL mailing list
>     Home: http://mailman.qth.net/mailman/listinfo/k3cal
>     Help: http://mailman.qth.net/mmfaq.htm
>     Post: mailto: K3CAL at mailman.qth.net mailto:K3CAL at mailman.qth.net
>     Unsubscribe: mailto: k3cal-request at mailman.qth.net mailto:k3cal-request at mailman.qth.net ?subject=unsubscribe
> 
>     This list hosted by: http://www.qsl.net
>     Please help support this email list: http://www.qsl.net/donate.html
> 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/k3cal/attachments/20200706/d885d023/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: QST_Mar_1960_p49_Long WIre for Small Lot.pdf
Type: application/pdf
Size: 816177 bytes
Desc: not available
URL: <http://mailman.qth.net/pipermail/k3cal/attachments/20200706/d885d023/attachment-0001.pdf>


More information about the K3CAL mailing list