In addition to the above posts, there are dozens if not hundreds of others available on this popular topic by searching:
http://www.eham.net/ehamforum/smf/index.php?action=search

You may have to spend a bit of time; some of the postings reference empirical data, but most anecdotal.

GL, 73, Rich, K3VAT

I stand corrected, didn't understand it without a picture - hi.  thanks.

Steve,
Yes, the premier of autotuners comes from Germany, the AT615B.  Rock solid in every detail; highest reliability, great customer service see: http://www.hamware.de/hardware/tuner615B/at615B-e.htm but you must be willing to pay top dollar ($2200 +).

GL, 73, Rich, K3VAT

Thanks Dale, but now we have separate two antennas - a parallel or fan dipole with a 65' (40M) piece of wire and another wire of 22' (15M).

I believe that the poster "[wants] to use a 40M dipole on 15M".  If a 40M dipole allows one to adequately load up on 15M, perhaps a decent match across most of the band, so why go to the trouble of adding a second piece of wire; what is really gained?  Adding the 2nd wire will produce a very noticeable interaction unless the arrangement is configured as a 90 degree fan dipole.

thanks, 73, Rich, K3VAT

I have not vertically stacked a HexBeam Antenna, but plenty of yagi arrays.

First, vertically stacking, while not exclusively done, is mostly relegated to monobander antennas.  This is because the 2nd antenna is tuned to the 1st to take advantage of the reinforcing amplitudes generated by each antenna.  The distance between them is primarily determined by which band you select and secondarily to the the antenna's gain figures.  To produce the additional gain (a maximum of ~ 3db) requires a specific RF relationship between the two antennas.  For example two M-Square 4 element 20M yagis have a stacking distance around 56 feet; other M-Squared 4 element yagis have significantly different stacking distances based upon their frequency of operation.

Moving the stacking distance a few feet either side of the recommended stacking distance will not substantially hurt their performance; but, if you stacked those 20M yagis (cited above) at 15' apart, they would not work properly and would actually perform worst than a single yagi.

I've read about a few operators who have stacked triband yagis (10M, 15M, and 20M) at a distance apart based on 15M operation and they have reported "very good" performance on 15M and "decent" performance on 10M and 20M.  IMHO, I don't think that you'd see this when using a HexBeam.

Perhaps G3TXQ will chime in on this ... he's much more familiar with HexBeams than most of us (especially me - hi).

GL, 73, Rich, K3VAT

That is correct as K2OWK pointed out.


Don't believe everything you read.  Adding that much wire to the 40M doublet will throw off the resonant of 40M and it will not be suitable for operation on 15M.  Specifically a 40M dipole is ~65' long; changing the length to ~78' now resonants the antenna at 6. mHz and the 3rd harmonic at 18. mHz (maybe good for 17M).  Creating some sort of 'bent dipole' doesn't significantly change this.

See the ARRL Antenna Handbook, Chapter 2 which covers the theory.

GL, 73, Rich, K3VAT

Yea, what band(s) of interest?  The Extended Double Zepp provides gain/directivity (see 8-40 of ARRL Antenna Handbook), but they're for single band, but can be made very stealthy.  There is a mini-Hex Beam from K5BOB that also may be of benefit in your search.

GL, 73, Rich, K3VAT

Please see this link:
http://www.eham.net/ehamforum/smf/index.php/topic,86091.0.html

Some kind of mitigation is definitely required if you are getting RF in the shack.
Snap-ons are good and may totally rectify the problem.  Place them at both ends: at the antenna closest to the feedpoint and at the input of the tuner.

Search this Forum for recommendations on good performing beads & mixes.

GL, 73, Rich, K3VAT

From DXWORLD :

Earlier reports suggested this call was a slim, however info received from the ZK3N team confirms that ZK3T is indeed Dieter, DJ2EH (ex-ZD9T).

He has been active on 15, 17  & 30M CW but his focus will soon be on Low bands.

ZK3T is QRV until February 20th. QSL via DJ2EH.

Very good postings!

It is not really "hard" - it is scarcity.  Sort of the amateur's version of Supply and Demand.  If all 340 entities were active, then DXCC HR could be earned very quickly, relatively speaking.  But that isn't the case.  Certain entities seem to be active only once per decade or more (such as Heard Is); others (N Korea) may be longer.  Arranging DXPeditions to the rare ones is a marathon (see N6PSE's recent & excellent postings on this subject) very time-consuming and extremely expensive.

The guys at HR#1 have been at it for multiple decades ... they had the opportunity to take advantage of the dwindling 'supply'.

GL, 73, Rich, K3VAT
334/334

If you are primarily interested in casual operation, then I vote for the DX-EE at 27'.  You may even hear some decent DX with this antenna, especially on 10M and maybe on 15M where the height is sufficient to radiate some low angled signals.  The other option is a trap dipole: either from a manufacturer or make-your-own for your favorite 3 or 4 bands (see Unadilla).  Use good coax (LMR400 is my choice).  GL, 73, Rich, K3VAT

IMHO, this is the best video on standing waves:

http://www.youtube.com/watch?v=DovunOxlY1k

a must view for anyone who wants to understand (or better understand) this subject.

Tim, 
Both these antennas have been extensively commented upon over the past couple of years.  You can use the eHam search engineer specific for this Forum and spend some time studying the comments/reviews/opinions. 
See: http://www.eham.net/ehamforum/smf/index.php?action=search.  I recommend checking out as many of these as possible, then come back to the Forum with specific questions.  That way your chance of getting meaningful comments is enhanced.  GL, 73, Rich, K3VAT

Short answer yes, definitely.  Do didn't mentioned the approx distance between houses and what bands that you're interested in operating - this is important because the lower the frequency the more closely located foreign objects, especially metal will interact.  On 10M you might be fine if you center the loop midway between two houses 30' apart (that's around 1/2 wave to the house).  However, on 80M these homes are smack in the middle of the near field and subject to far more degradation.


Wood vs concrete is very minor.  The major concerns are conductive structures such as metal rain gutters and downspouts, aluminum sliding, metal frame windows and doors, house a/c wiring, cabling for telephone/satellite/internet, and metal poles and support beams commonly found in basements (supporting the above floor(s)).  Additionally, what about common utility runs such as gas, water, electricity, telephone that often run between or nearby dwellings?

Any chance of a roof-mounted structure? 

GL, 73, Rich, K3VAT