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elfwa revisited

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kc5wa

elfwa revisited

Please me revisit the EFLWA for a moment. In the KXAT1 manual page 9
shows a random
length wire in a tree. For 40/30/20 a wire length of 24-28' is
recommended. Ground
system use one radial cut to at least 1/8 wave length on lowest band
used (16' on 40m)
page 10 shows a Pomona model 1296 double binding post. Since I suffered
an attack of
senility when I ordered my K1-2 (I ordered it with 80m and 40m) and a
KAT1. I wish to
utilize a random length wire for it Should it be double the KXAT1's
recommendations
(48-56') with a ground system of 1/8 wavelength on the lowest band (32'
on 80m)
double that of 40/30/20m.
tnx es 72/71
de "rc"kc5wa

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Don Wilhelm-3

RE: elfwa revisited

RC,

Yes - double the length and try it, a 48-56 ft random wire with a 32 ft
radial should load fine on 80 and up. If you find it out of the range of
the KAT1 or KXT1 tuner, just extend is a few feet at a time until you
discover a length that works for you.

Thia is a 'random wire' antenna, it is not an EFLWA which is a more specific
term for antennas that are 1 wavelength or more at the lowest frequency.
The radiation pattern from an End Fed Long Wire Antenna is quite specific
and has lobes at specific and predictable angles from the wire (making it a
directional antenna) - the exact angle depends on the number of half
wavelengths of the wire. It is this directionality that is the desirable
quality of the EFLWA, quite apart from the means of feeding it. A really
long long wire antenna can rival a beam in its favored direction, and I'm
certain you have heard rave reports about the performance of large rhombics
which are close cousins to the long wire antenna. There is a whole chapter
in the ARRL Antenna book devoted to these Traveling Wave antennas - they
work great if you have the space.

73,
Don W3FPR

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf Of Robert Conley
> Sent: Saturday, March 26, 2005 11:47 PM
> To: elecraft@Elecraft List
> Subject: [Elecraft] elfwa revisited
>
>
> Please me revisit the EFLWA for a moment. In the KXAT1 manual page 9
> shows a random
> length wire in a tree. For 40/30/20 a wire length of 24-28' is
> recommended. Ground
> system use one radial cut to at least 1/8 wave length on lowest band
> used (16' on 40m)
> page 10 shows a Pomona model 1296 double binding post. Since I suffered
> an attack of
> senility when I ordered my K1-2 (I ordered it with 80m and 40m) and a
> KAT1. I wish to
> utilize a random length wire for it Should it be double the KXAT1's
> recommendations
> (48-56') with a ground system of 1/8 wavelength on the lowest band (32'
> on 80m)
> double that of 40/30/20m.
> tnx es 72/71
> de "rc"kc5wa
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>

EricJ-2

RE: elfwa revisited

My last year in the Army (1965-1965) was as one of three operators at K2USA
at Fort Monmouth, NJ. We had monobanders (Telex) on 90' poles for 20-2m and
6 professional studios full of Collins and Hallicrafters equipment to feed
them.

But the most impressive and very well known antenna at K2USA was a rhombic,
one of the few amateur band rhombics in existence. It was also on 90'
telephone poles. It terminated on Europe, but could be switched to radiate
the other direction. Some late nights I would tune around 20 when it was
dead. Sometimes I would hear two VK's working each other on ground wave and
thinking the band was closed. Not for that rhombic, an S-Line and a 30L1.

Tough duty, but a soldier goes where he's needed.

Eric
KE6US

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of W3FPR - Don Wilhelm
Sent: Sunday, March 27, 2005 4:56 AM
To: Robert Conley; elecraft@Elecraft List
Subject: RE: [Elecraft] elfwa revisited

RC,

Yes - double the length and try it, a 48-56 ft random wire with a 32 ft
radial should load fine on 80 and up. If you find it out of the range of
the KAT1 or KXT1 tuner, just extend is a few feet at a time until you
discover a length that works for you.

Thia is a 'random wire' antenna, it is not an EFLWA which is a more specific
term for antennas that are 1 wavelength or more at the lowest frequency.
The radiation pattern from an End Fed Long Wire Antenna is quite specific
and has lobes at specific and predictable angles from the wire (making it a
directional antenna) - the exact angle depends on the number of half
wavelengths of the wire. It is this directionality that is the desirable
quality of the EFLWA, quite apart from the means of feeding it. A really
long long wire antenna can rival a beam in its favored direction, and I'm
certain you have heard rave reports about the performance of large rhombics
which are close cousins to the long wire antenna. There is a whole chapter
in the ARRL Antenna book devoted to these Traveling Wave antennas - they
work great if you have the space.

73,
Don W3FPR

> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]]On Behalf Of Robert Conley
> Sent: Saturday, March 26, 2005 11:47 PM
> To: elecraft@Elecraft List
> Subject: [Elecraft] elfwa revisited
>
>
> Please me revisit the EFLWA for a moment. In the KXAT1 manual page 9
> shows a random length wire in a tree. For 40/30/20 a wire length of
> 24-28' is recommended. Ground system use one radial cut to at least
> 1/8 wave length on lowest band used (16' on 40m) page 10 shows a
> Pomona model 1296 double binding post. Since I suffered an attack of
> senility when I ordered my K1-2 (I ordered it with 80m and 40m) and a
> KAT1. I wish to utilize a random length wire for it Should it be
> double the KXAT1's recommendations
> (48-56') with a ground system of 1/8 wavelength on the lowest band (32'
> on 80m)
> double that of 40/30/20m.
> tnx es 72/71
> de "rc"kc5wa
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>

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G3VVT

Re: elfwa revisited

In reply to this post by kc5wa

In a message dated 27/03/05 18:21:39 GMT Daylight Time,
[hidden email] writes:

But the most impressive and very well known antenna at K2USA was a rhombic,
one of the few amateur band rhombics in existence.

---------------------------------------------------------

1981 to 1985 I lived in Dhahran, Saudi Arabia and was a member of the HZ1AB
club. We had a 20m rhombic pointed right back at K2USA that was shared with
the US military. The performance of this was phenomenal, far better than the
KLM KT34 that was up on the tower. I used to switch of the linear amp when
operating with the rhombic and use the Collins KWM2 or the TS-430 we had at the
time barefoot, otherwise we attracted far too many callers making copy
difficult. I was moved across the country in 1985 to a new job on the Red Sea coast
at Yanbu, over 1000km away and lost touch with the club. Last I heard in
September 2004 was that the HZ1AB licence has now been reassigned to a Saudi
national and the club station closed down. There are pictures of the HZ1AB
rhombic on the HZ1AB website when the station was moved from the old Dhahran
airport into Dhahran airbase:

www.qsl.net/hz1ab/

The old rhombic was on 40 ft wooden power poles across the car park in front
of the old Dhahran airport domestic terminal entrance. Looks something like
110ft wooden poles were used at the new location in the airbase.

Bob, G3VVT
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EricJ-2

RE: elfwa revisited

Very nice. Thanks for the URL, Bob.

I haven't been back to K2USA since 1985. I understand that since then the
rhombic has been let go to seed. The poles are overgrown with vines and I
believe some of the wires are broken. What a shame. It was a highlight of my
ham life to use that thing. I didn't need to use the 30L1 with it, but, I'm
sorry, when you got it you flaunt it. hi.

Eric
KE6US

_____

From: [hidden email] [mailto:[hidden email]]
Sent: Sunday, March 27, 2005 4:17 PM
To: [hidden email]; [hidden email]
Subject: Re: [Elecraft] elfwa revisited

In a message dated 27/03/05 18:21:39 GMT Daylight Time,
[hidden email] writes:

But the most impressive and very well known antenna at K2USA was a rhombic,
one of the few amateur band rhombics in existence.

---------------------------------------------------------

1981 to 1985 I lived in Dhahran, Saudi Arabia and was a member of the HZ1AB
club. We had a 20m rhombic pointed right back at K2USA that was shared with
the US military. The performance of this was phenomenal, far better than the
KLM KT34 that was up on the tower. I used to switch of the linear amp when
operating with the rhombic and use the Collins KWM2 or the TS-430 we had at
the time barefoot, otherwise we attracted far too many callers making copy
difficult. I was moved across the country in 1985 to a new job on the Red
Sea coast at Yanbu, over 1000km away and lost touch with the club. Last I
heard in September 2004 was that the HZ1AB licence has now been reassigned
to a Saudi national and the club station closed down. There are pictures of
the HZ1AB rhombic on the HZ1AB website when the station was moved from the
old Dhahran airport into Dhahran airbase:

www.qsl.net/hz1ab/

The old rhombic was on 40 ft wooden power poles across the car park in front
of the old Dhahran airport domestic terminal entrance. Looks something like
110ft wooden poles were used at the new location in the airbase.

Bob, G3VVT
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Rich Ardolino

Re: elfwa revisited

In reply to this post by kc5wa

The K2USA rhombic still exists. My local ham club, Garden State Amateur Radio Assoc. has it's monthly meetings at the MARS station at Ft. Monmouth, and we ocassionally operate the station. I've hooked my K2 to the rhombic and it really turns the mojo loose. Lately the rhombic is "down" due to some broken wires but in the near future GSARA plans to effect repairs to it and some other K2USA antennas as well. We hope to have K2USA up and running for field day as a class F (EOC) station.

Elsewhere on the Ft. Monmouth base, GSARA is planning to set up a battery powered QRP station using the club call W2GSA, and my K2 is "drafted" for the effort.

Rich K2CPE
K2 #1102

-------------- Original message --------------

>
> In a message dated 27/03/05 18:21:39 GMT Daylight Time,
> [hidden email] writes:
>
> But the most impressive and very well known antenna at K2USA was a rhombic,
> one of the few amateur band rhombics in existence.
_______________________________________________
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