Same.

My Bad.

Typo'd your call in a lookup as 'RJX which gave you a QTH and sex change, but aside from that...

I see that you're in Dallas, which is close enough to the center of this great circle map to be relevant...

http://www.qsl.net/crosscarc/GreatCircle.html

Short path to EU is @ 40 degrees relative to true north, meaning if your dipole could run along a NW - SE line that would be about right. As for time, Central Europe (Germany) runs seven hours ahead of CST, Western Europe six hours. Noon in Dallas is 7pm in Munich and Saturday / Sunday mornings are probably your best bet.

As for the band, the highest frequency band that's open is usually a good starting point.

Cebick does good work.

I stop by every few months just to see what's new and  like that he isn't partial to any particular antenna type, isn't selling anything and is consistent enough in his analysis for direct comparisons.

He's also up front enough to tell you how EZNEC can be misled.

The goal here is an all-band no-tune wire antenna that can be put together with parts on hand. Will there be tradeoffs in efficiency, radiation angles and pattern from one band to the next? Absolutely... Same as any other antenna.

The reason I asked the question is to solicit opinions on how significant the tradeoffs between performance and convenience might be and to see if anyone comes up with a consideration I haven't thought of.

It's a cold day today and thumping a keyboard is more fun than rigging wire. Given the way the HF bands are at the moment no matter what I put on the air it's likely to perform poorly, so cut & try is the long path to 'getting there'.

As for rhombics, there's more to the design than a Hi-Z dummy load with radiating elements. The diamond shape is intended to combine the field strength of the four elements into a desired pattern. I have some old Signal Corps manuals on the topic and if you run the numbers it's possible to design a rhombic to plunk a signal down just about anywhere you want it, assuming average condx. Something like 15 years ago QST ran an article about a VOA site in Ohio that was in the process of being torn down and the local ham club got permission to use the antenna farm on a Saturday. We're talking heuuuuge rhombics @ 170' tweaked for various points on the compass and they alligator-clipped a 100w transceiver on to the wire aimed at EU. The results were incredible... Couldn't work anything on the east coast and heard almost nothing from the US, but it was like being a fly on the wall in downtown Stuttgart. Worked everything they heard in central Europe with bodacious signal reports coming back on an otherwise mediocre day.

If I had 100 acres and a budget approved by Congress that might be an option for me, but I have a hunch that ain't happenin' any time soon.

So, I'm kicking around ideas in advance of warmer weather...

Thanks, Dave... That's exactly what I was looking for in terms of expected radiation efficiency and matching. I figured it would be a cloud burner on 160 / 75 but expected better on 40. I'd be better off with the 136' off center fed dipole I had a few years ago or a classic all-band doublet. (136' tip to tip, 66' balanced line feeder)

If you could, do one more run through EZNEC for me...

I can do an alternate loop configuration using the same two masts and the chimney of the house as a third support. Almost an equilateral triangle, 100' of wire running north-south, 90' of wire on each side pointing to the feed point due east. This time the loop is parallel to the ground and around 28' up. What happens to the elevation angle on 40 and up, what do the gain numbers look like?

I can be happy going back to the OCFD except I'd have to get fancy to make it play on 15. The doublet idea is a proven classic but running a balanced line to the shack would be difficult for me and I'm not in love with the idea of an auto-tuner tucked under an eave. Yeah, that could be an option, but it adds cost, complexity and one more thing to go toes-up after a near lightning strike.

Thanks again for running the numbers...

20-something years ago I had to run some Cat-3 through walls from time to time and found the best way to fish the actual wire between the studs was to drop a small chain down the access hole that I drilled. Heavy enough to drop straight, flexible enough to avoid a snag, if your holes don't exactly line up push a pencil through the chain to hold it up top then 'stroke' the wall with a magnet to steer the chain where you want it.

A string and plumb bob can do the same, but if the chain hangs you can jiggle it and usually hear where its hung up.
 

The terminating resistor makes the loop non-resonant and broadband, much like a rhombic or terminated folded dipole. Considering that I have a 280' piece of 10ga on hand (zero dollar engineering) the non-radiated power absorbed by the terminator should be progressively less as I QSY up through the bands. 280' is a shade over a half wave on 160 and a full wave on 75.

As for a tribander @ 40'... I don't want the cost, maintenance or liability. Have the masts, have the wire, have the balun cores, have the coax. Also have a dozen or so 400 ohm 40 watt non-inductive resistors so I can do series / parallel combo's for 200, 400, 600, 800 ohms, etc. The only expense would be for the rope and setup time.

The double balun thing does concern me, but according to Sevick if I wind 'em right and the impedances come out near where they should be the total insertion loss is less than half a dB for the baluns. The transceiver does have a built in tuner, so that's an option in case Murphy gives me a hand, but if I can come out flat enough for plug & play that's one less loss in the chain.

I used to play with the 10 Meter AM'ers on Sunday afternoons back when 10 was open most of the time and got good audio reports with an IC-756 after I turned off the speech compression. Best guess is the compressor limits the audio bandwidth and clips a bit much for AM.

Carrier was set to maybe 25-30 watts as I don't like pushing a transmitter to the max. The output meter showed 85-90 watts PEP on peaks which is about what I run on SSB. Played well. When the bands are open leaving a few watts for headroom won't hurt a thing.

Gentlemen:

I am blessed with a modest chunk of real estate that's on the back end of a cul-de-sac so it's pie shaped and has a long-ish run of fence aligned exactly on a north-south axis. A few years back I put in a pair of 30' telescopic TV masts 120' apart and hung a 136' off center fed dipole across them. Yeah, the ends drooped a bit and I had 5' of PVC on top of the metal for a bit of separation so the whole mess was 32' or so above the ground.

Worked well. Q'd the world during Cycle 23 with 100 watts. Two years ago a large-ish neighbor's tree split during a storm and took out the south mast. Now that Cycle 24 is on the way I'm thinking of how to re-do The Wonder Wire.

Thot: Visualize 280' of 10ga stranded copper arranged as a rectangle approximately 110' horizontally and 20' high, top wire is maybe 28' off the ground, bottom wire is around 8' up. The vertical rectangle is aligned true north-south along the plane of the wire. At the center of the bottom wire is an insulator and 800 ohm non-inductive resistor. At the center of the top wire there will be an insulator and home-brew open wire line  that runs maybe 60' to the house. At that point under an eave there is a dual core 4:1 Guanella current balun transitioning from the open wire line to a siamese pair of RG-62 (92 ohm) coaxial cables arranged as a shielded pair running through the attic to the radio room. The shields are tied together and grounded at both ends.

At the transceiver end of this mess will be another 4:1 dual core current balun making the transition from the two coax center wires to a PL-259. The concept here is ~800 ohms to ~184 ohms to ~50 ohms across two baluns, the goal is semi-decent all band HF coverage of 160 through 10 Meters.

Yes, I know the antenna is too low for serious DX on 160 and 75, might be a player on 40, could start to shine on 20 and up. Putting the feed line on the top wire does two things: Elevates the line well above the pedestrian hazard level and should put the most RF current at the greatest height. Patterns will range anywhere from pregnant blob to fat figure eight to June bug on a windshield depending on the band.

Question: Assuming the large-ish terminated loop is fairly non-resonant and mostly flat impedance wise, and the baluns aren't being asked to perform a miracle, will my feed losses be reasonably low?

Essentially what I'll have is a stretched terminated folded dipole 110' long with 20' of separation between the horizontal wires. Is an 800 ohm terminator a good starting point? The ratios work well with that number. Since the terminator on the bottom wire it's within stepladder height for tweaking, but I'd just as soon hit it about right the first time...

W8JJI wrote:
"Envision a pair of 20 or 17 meter 4 element monoband yagis mounted side by side, vertically on a horizontal boom of about 35 feet end to end."
__________________________________________________

Got the picture, and know that anything can be done if you throw enough time and money at it, but OMG what a modest wind gust could do in terms of rotational torque on the tower and rotor... I'm visualizing a pair of 17' breaker bars with unequal wind catchers mounted on the ends. ( ! )

In the land of the tornado some of us think that way...

I can think of another possibility... Is there a balun anywhere between the radio and the HO loop? It has been a while since I've spent some quality time with Jerry Sevick's book on the subject, but do recall that a typical HF balun challenged by a hairy mismatch or pushed beyond its nominal frequency range can add distortion(s) to the radiated signal.

Is the HO loop we're talking about also used on HF? With the broadband nature of a big HF loop (very big @ 50 MHz?) and a balun that's misbehaving the spurs have a chance of doing some business around the neighborhood and beyond.

Anyone else been there, done that?

An aluminum paste would likely be the better choice as it avoids the possibility of electrolysis from dissimilar metals when wet. I used to use NoAlOx on every connection within an antenna until I discovered that it tends to migrate where I don't want it... Like into a gamma match or SO-239 connector block. Does a good job of attracting dirt if it gets on an insulator, too.

Chances are I'll be doing some antenna refurbing this spring and will likely use a graphite or molybdenum grease... Sparingly.

I'm having some problems getting the .PDF's to load, like maybe the web site is a bit gassy tonight, but poke around here

http://www.cpii.com/library.cfm/9

to see if you can pull up the conditioning, care and feeding, extending tube life topics.

Looked at some other links and they tell me that in the case of glass tubes the factory does a filament stress test (overvolt) and tube aging procedure before the part is shipped. Ceramic tubes should get a factory burn and spec check, especially on the high-dollar items... If it were me I wouldn't want to see them come back with a nastygram from the customer.

And W8JJI brings up a good point indirectly... In the case of long-ish SSB work on 2 Meters anything over 60 miles or so is probably over the horizon for the typical Q.

If you're relying on reflection or refraction to make the path, can you rely on the polarization remaining intact? Or that the beam heading that worked so very well last night is going to work tonight?

Disclaimer: I have no 2 Meter SSB rig and the closest direct experience I have is on 6 Meter SSB where propagation is whatever it wants to be. Not where, when or what I want it to be... Every CQ is a fresh roll of the dice.