HF WIRE ANTENNAS MADE IN GERMANY
HF WIRE ANTENNASMADE  IN  GERMANY

NEWS FLASH  New QRP RIG:

"SKY-SDR"

 Simply the Best ...   Better than all the Rest  in  its  Price  Class.

Photo:  DJ0IP

THIS PROJECT IS READY TO GO!

Unfortunately we have encountered a couple of delays.

  • First, I hurt my knee (actually the meniskus) and was on crutches for about a month.
  • Then I got involved in bringing the SKY-SDR QRP radio to market.  It turned out to consume most of my spare time, so I did not find time to begin work on the 807-UL.
  • Then the winter months arrived.  We build the 404-UL antennas here in Franken (middle of Germany) but we do not have room indoors to measure the 80m version.  It must be measured outdoors and it is simply too cold and wet at the moment.  We have enough space indoors for building the 40m version so there is no delay on it.

MODEL 807-UL

UPDATE:

 

On Saturday, 11-JUN-2016 I finally CONCLUDED this project.  Besides finishing the balun and associated matching circuitry of its Primary Matching Unit (PMU), one week earlier, I also finished the Remote Matching Unit (RMU).  The initial protype is 100% up and running to 100% full satisfaction.

 

THIS ANTENNA NO LONGER REQUIRES AN ADDITIONAL RF CHOKE - I HAVE SOLVED/FIXED THAT PROBLEM.

 

Now the bad news:  With only 2 weeks to go until Friedrichshafen, Spiderbeam will only be able to announce the product.  They will not be able to deliver units for sell at the hamfest.  However they will have my original prototype on display . . . with the PMU and RMU well encapsulated so that nobody can see what I have done to make this antenna work.

 

"SHIT WEATHER"

I honestly cannot remember a worse spring than this year (2016).  Last year I was out in the field measuring antennas in the 2nd week of March.  This year my first day in the field was May 28th.  That set us back significantly.

 

But now we are rolling and within a few months, Spiderbeam will be selling this new antenna which I must say, turned out much better than I had ever dreamed it could be.

 

 

Aerial-51 Model 807-UL

Several 404-UL users have asked for an 80m version of this antenna.

The first prototype is in the air now and already meeting the specifications shown below.

 

It took me 15 months to evolve the 404-UL into the 807-UL.  I learned several lessons in the process, which I plan to one day describe in a book on OCFD antennas.

 

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GENERAL DESCRIPTION:

 

The 807-UL is based on the same technology as the 404-UL, is twice as long, and has a modified balun which better matches the common mode current characteristics of this antenna.  It is SIGNIFICANTLY different.  

 

In addition, in order to have higher bands in resonance, it was necessary to set the 80m resonance low, very low; below the amateur band.  Resonance was initially at about 3.450 MHz... much lower than anyone would expect . . . or accept.

 

Obviously I could not leave it like this so a method was sought and found to raise the 80m resonance WITHOUT changing the resonance on other bands.

 

In the meantime I have developed a method to enable me to set 80m (or 75m) resonance anywhere I desire, without affecting the frequency of resonance on any of the higher bands.

 

Like the 404-UL, the 807-UL is purpose designed for the traveling ham who needs an ultra lightweight antenna, but also needs 80m. 

AND OF COURSE IT INCLUDES 15m!  It would not be an Aerial-51 antenna without 15 meters!

 

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PERFORMANCE:

 

Like the 404-UL, the 807-UL has what it takes to be a great performer.

It has no traps . . . but this time I did need a gimmick to achieve all goals. I'm sure many people are curious to learn how I did this, but I'm afraid I must disapoint you; I am not going to divulge this information at this time.

 

It's no secrete, performance comes from erecting the antenna high into the air, thus reducing ground losses and enabling a lower angle of radiation.  

No combination of tricks, magic or marketing hype can replace this, regardless of how much money you spend on other toys.  Therefore the weight of the 807-UL has remained exceptionally low for an antenna covering 7 (8) bands.

 

WEIGHT:  I cannot tell you what the ultimate final weight will be.  My prototype weighs only 488 grams including 50 ft. (15m) co coax, but the balun is "open frame" (i.e. not in a box).  Spiderbeam will enclose the balun in a box and probably add another 100 gr. of weight, making this 50% heavier than the 404-UL . . . still, a very respectable lightweight ALL BAND antenna.

 

ALL BAND:  "almost"  I did not manage to get 30m to work with this antenna [yet].  I have one more idea to try but it will be later this year. For now it is important to finally get this antenna to our waiting comunity of users.

 

HEIGHT IS MIGHT - PERIOD.

 

For portable antennas, "ultra-light" is key for enabling height.

 

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PRELIMINARY  SPECIFICATIONS:

  • 7 Bands:  80/40/20/17/15/12/10m . . . plus usable on 6m.
  • SWR less than 2:1 on all bands except 12m; generally much better.  
  • Power:  200w  SSB and CW
  • Length:  ca. 40.7m  (134.5 ft. - full-size on 80m)
  • Weight:  about 600g / 21oz.  (depends on how Spiderbeam decides to implement the balun)
    • NO MORE CHOKE NECESSARY.  I HAVE SOLVED THAT PROBLEM!
  • Length of Coax included:  15m (50 ft.)
  • ALL OF THE ABOVE IS SUBJECT TO CHANGE - but not by much... at the descretion of Spiderbeam!

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ESTIMATED  COMPLETION DATE:

  • NOW:  I am done.  The antenna works great.  I am waiting for Spiderbeam to ramp production.

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ESTIMATED AVAILABILITY (Date:)

  • CURRENTLY NOT POSSIBLE TO SAY.
  • Rough guess:  November 2016

 

SNEAK PREVIEW:

 

CAUTION:  30m only "looks" good.  This is due to the impedance transforming of the feedline.  The SWR on that band at the feedpoint is nearly 10:1, so this is NOT a good antenna for 30m.

 

 

Now the nitty gritty.  The curves below are the final results of my 15 months of development on this antenna.

 

HEY USA!  We realize most of you do not work CW and must have 75m coverage.  To enable you to do so, we will have a version of the antenna which is much more suitable for working 75m emergency frequencies WITHOUT disturbing the resonance on the other bands.

 

Here is what it can look like:

 

I have concluded my work.  It remains to be seen how Spiderbeam decides to market and sell this antenna.

 

Thank you for your interest in my design.

 

73

Rick, DJ0IP


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