long wire for 6 or 2 meters

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Allison:
I disagree. Within limits wire at VHF is a serviceable antenna.

I do agree that feeding it as a multiband is not going to happen unless you try an off center fed windom.  I think that would be a bit fussy for 6&2.  In either case a coax feed to the long wire is out of the question unless the match point is at the antenna.

I've used wire antennas at 6m successfully.  I currently have a folded dipole with twinlead feed to a matching section balun and coax, an EDZ (~24ft) with a stub match and coax fed (stub is my tuner) and an ~75ft long wire in a inverted L config (match at the base).  All work, they favor differing directions. Though the only one that I consider for other than local is the EDZ, It has enough lobes to be near omni, The EDZ compares well enough to the 3element 6m beam that I use it for listening to the band for openings on the #2 RX.  No question the trick in all cases was getting the match to work out.

At 2m and above beam antennas get small enough to not bother. Check out the Clear Lake ARC as Kent Britan did some nice cheap reproduceable beams that are small and effective.  I've built the VHF and UHF versions for field and other portable uses, they perform well.

Steve Katz:
KB1GMX, the question involved a "long wire" antenna.  By definition, that's a wire that's wavelengths long and fed at one end, which excludes EDZs, Windoms, folded dipoles and other designs.  A long wire is a long wire, and after 38 years of working 6 meters, I've never found one to work worth a darn -- at least, not compared to anything else.

A 1/2-wavelength center-fed dipole can be a highly effective 6m antenna, especially if you can rotate it and install it up in the clear of nearby obstacles.  An EDZ or OCF doublet (which many call a "Windom" design, although any doublet fed with a transmission line is technically not a Windom at all) can work as well as a 1/2-WL dipole, but it would be rare for it to work better at 50 MHz: An OCF doublet is still a 1/2-WL antenna, with identical aperture and pattern to a 1/2-WL dipole -- the only difference is where it's fed.  An EDZ can have a tiny bit of gain over a 1/2-WL dipole, but that gain is in only two directions, and doesn't favor the antenna's broadsides.  It's also larger and more difficult to rotate, and thus rarely provides any performance improvement over a conventional 1/2-WL dipole at 50 MHz.

This isn't theory speaking (although theory does support my contentions), it's experience and performing real-world antenna range tests at the Central States VHF Society meets and elsewhere over a period of more than thirty years.

"Everything works," for sure (as N6BT wrote for a famous QST article), but until one has a serious six meter antenna, he'll never know what he's missing.  

WB2WIK/6



Allison:
I disagree. Experience and on air use.

I look at it this way.  Wire is cheap, it can be effective if used right.  At higher frequenies matching may be a challenge and lengths more critical.

Other caveats.
  The formula 486/f is lousy at VHF as K factor (diameter of element to wavelength) becomes more significant.  Use that formula, plan to trim.  I'd go further to say any formula that works at 20m
will maybe get you close at 6m and nowhere at 2m.

  At 2m and above, why bother with simple wire?  A few feet of #10 and a peice of wood can yeild a good 3 or even better 6 element beam that is less than 41" wide by 70' long.  At 432 you're down to 13" wide by under 4ft for 9-11 elements and good gain.

What I've fould and verified:

As mentioned I do have a longwire, it works.  Works defined as good for local contacts (30+mile radius) at low power (under 10W) and directional as all getout as it fires off the far end. It's aimed west.  It was hardest to tune at 4+ waves long.  It's an ok antenna as it serves for a general use wire for other bands.   If there is a complaint, using 80ft of wire in a colinear config would get near twice the gain.  It's not efficient use of wire for the gain(low).

Dipole, easiest to make and match.  Small, no gain and works for local and E openings. It is the least used of the three wires but the first 6m specific antenna I put up.

EDZ, NOT the usual 102ft thing (g5rv elal).  This is a 1.5Wave center fed doublet with a stub to match it for coax feed with bazooka balun. Works fine for the SSB segment for which it's tuned. It offers significant gain over a bare dipole (4.5->5db by substitution using same radio and attenuator.) It's about 24ft long and could be made of tube and rotated but the 3 element beam is smaller. It has a different pattern than the dipole but the lobes have more gain.  It's only 18ft up and lowest of the three wires.  It's oriented nw/se for use to the east and west.  Seems to hear and talk to Florida and Nebraska ok when sporatic Es happen.  It's a better listening for openings  antenna than either beam due to the multiple lobes (less directional).

All of the wire antennas (LW, EDZ and Dipole) are inferior to the 3element yagi for front to back and gain in the favored directions.  For serious stuff the 4element does help as it's highest and turns.  

I may be odd as I have a total of 5 antennas for 6m use and each is useful for different things depending on direction, incomming angle, mode of propagation and source of local noise.

Allison

Nick:
dipole for 6 meters is very easy, i cut a 9 foot wire in half used insulaters and coax with feed to one side and shield to the other and put it up about 18 to 20 feet and my first contact was with m1ers in shuffield england, been having fun ever since, i moved on to build my 3 element beam and stacked loops.
have fun
w3nrl
ps. i used a 2 meter homemade beam for 2m ssb and 70cm homemade for 70cm ssb ( i make all my beams and antennas)

:
I'm going to agree with Steve, WB2WIK/6, that a long wire is a crappy antenna at VHF frequencies.  A 1/2 wave dipole or a loop will do much, much better.  That is also based on experience on the air and plenty of A/B tests.  Even the loss associated with adding a tuner makes a difference at 144MHz.

I really do recommend loops for omnidirectional, inexpensive, easy to build antennas at 6m and above.

Oh, BTW, a limit of 30 miles for "local" contacts does sound pretty darned limiting to me.  With a 3 element beam at 30' I can consitently work a couple of hundred miles out under pretty well dead band conditions on 6 even with just 10W of power.  A loop doesn't do quite as well, but it isn't bad either.

73,
Caity
K7VO

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