My vertical antenna for the demonstraion was not a BigIR. I believe the
CrankIR vertical is rated 1500 watts, but have not tried it using that much
power on RTTY.
Keith NM5G
From: john@kk9a.com [mailto:john@kk9a.com]
Sent: Thursday, December 7, 2017 8:56 AM
To: Keith Dutson <kdutson@sbcglobal.net>
Cc: turnbull <turnbull@net1.ie>; towertalk@contesting.com
Subject: Re: [TowerTalk] BigIR question
That is surprising, can the SteppIR designs be used for legal limit RTTY?
John KK9A
Sent via the Samsung Galaxy 7 edge, an AT&T 4G LTE smartphone.
On Thu, Dec 7, 2017 at 9:52 AM, Keith Dutson <kdutson@sbcglobal.net
<mailto:kdutson@sbcglobal.net> > wrote:
That sounds reasonable. You might want to contact SteppIR to help detect the
problem.
I was using a vertical antenna rated for 1500 watts, but it failed using 1500
watts AM on 80 meters. SWR went very high causing amp (Alpha 87A) to fault.
Manufacturer said it would not handle AM, only PEP. So much for my
demonstration to a friend. <grin>
73, Keith NM5G
From: turnbull [mailto:turnbull@net1.ie <mailto:turnbull@net1.ie> ]
Sent: Thursday, December 7, 2017 2:07 AM
To: Keith Dutson <kdutson@sbcglobal.net <mailto:kdutson@sbcglobal.net> >;
john@kk9a.com <mailto:john@kk9a.com> ; towertalk@contesting.com
<mailto:towertalk@contesting.com>
Subject: RE: [TowerTalk] BigIR question
Starts at about 1.2 and heads for 2 to 1. The BE is maybe 20 kHz. This is a
Hi Q device when using the loading coil. 73 Doug EI2CN
Sent from my Samsung Galaxy smartphone.
-------- Original message --------
From: Keith Dutson <kdutson@sbcglobal.net <mailto:kdutson@sbcglobal.net> >
Date: 07/12/2017 00:58 (GMT+00:00)
To: 'Doug Turnbull' <turnbull@net1.ie <mailto:turnbull@net1.ie> >,
john@kk9a.com <mailto:john@kk9a.com> , towertalk@contesting.com
<mailto:towertalk@contesting.com>
Subject: RE: [TowerTalk] BigIR question
What is your SWR on 80?
Keith NM5G
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Doug
Turnbull
Sent: Wednesday, December 6, 2017 9:56 AM
To: john@kk9a.com <mailto:john@kk9a.com> ; towertalk@contesting.com
<mailto:towertalk@contesting.com>
Subject: Re: [TowerTalk] BigIR question
Dear OMs and YLs,
I have a BigIR mounted on an extensive radial field and also with the
80/60M loading coil. In contests, I am allowed to run 1500W - I find that
on 80M the antenna does not stay in tune while transmitting for a while and
assume this is to do with heating but am not sure. Normally I would not
operate with more than 500 W for a contest on 80M then there is no problem.
On 40M to 10M there is no such problem.
This is not my prime antenna but is a useful fallback. It is an
excellent vertical.
73 Doug EI2CN
PS Only in contests are we allowed this higher power level.
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
john@kk9a.com <mailto:john@kk9a.com>
Sent: 06 December 2017 12:23
To: towertalk@contesting.com <mailto:towertalk@contesting.com>
Subject: Re: [TowerTalk] BigIR question
This is a much better antenna than the fixed height 43' vertical that is so
popular.
John KK9A
To: Frank VO1HP <invl160@gmail.com <mailto:invl160@gmail.com> >
Subject: Re: [TowerTalk] BigIR question
From: Ed Richardson <ed_richardson@shaw.ca <mailto:ed_richardson@shaw.ca> >
Date: Tue, 5 Dec 2017 19:44:07 -1000
Jim. The bigIR can be tuned to a quarter wave on all frequencies from 7 to
54 MHZ. On frequencies from 21-54 MHz you can select a 3/4 wavelength mode.
I have used this antenna with raised radials, tuned stub radials and a
ground mounted radial field. Works well in all cases. It is still a
quarter wave vertical.
No magic
Ed. Ve4ear
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com <mailto:TowerTalk@contesting.com>
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com <mailto:TowerTalk@contesting.com>
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|