AVAILABILITY UPDATE: 807-HD: April, 2018 /\/\/\ 807-L: May 2018
+30m with reduced power
Power ("-L" & "'HD"):
500 Watts SSB/CW
100 Watts on 30m
Length: 40,6m (133')
Weight: 600g (1 lb. 5 oz.)
Pictured Here: 807-L --> -->
See also 807- HD, HP, LP, UL in the menu on the left.
DOWNLOAD MANUAL: PRELIMINARY USER MANUAL
DOWNLOAD BROCHURE: MODEL 807-L BROCHURE
The 807-L is the first 80m product out of the chute, and the 807-HD will be available early Q2-2018.
After careful consideration of the market needs, it was determined that there is not enough commercial demand for an ultra-light 80m antenna. SOTA goats simply do not remain on the mountain top until after dark.
At the same time we have seen lots of demand for an antenna that can handle more power, especially in RTTY mode.
The 807-L is identical to the original 807-UL plan, but has a beefed up purpose-designed "Hybrid Balun"... with power handling of:
The total weight will be ABOUT 600 grams (21 oz.) just 150 g (5 oz.) more than the originally planned 200w "UL" version.
We will maintain the same stealthy thin wire planned for the "UL".
When hung from a tree at 12m (40') height, nosey neighbors can hardly see the antenna!
In addition, we have added useful features for the international community:
Our challenge with this antenna "was",
We believe we have found a suitable solution for both regions.
The "Remote Matching Unit" (RMU).
The RMU is just 25cm (10") long and weighs just 34g (~1 oz.).
In the 807-L drawing below, you will see an RMU located in the longer leg of the antenna. This RMU is easily interchangable, and field-replacable. It is a selectable (but manditory) option, for setting resonance to :
( THESE ARE ONLY BALLPARK NUMBERS )
( First ship has resonance at 3.670 MHz )
(Resonance varies slightly from one QTH to the next.)
Buyers will have a choice of which RMU they want.
When purchasing the antenna, simply state which RMU you want. Should your needs change later, you may simply swap the RMU for another. The price will be reasonable.
NOTE: Unlike normal dipole antennas, you MUST NOT attempt to adjust resonance by changing the length of the antenna legs. This will quickly cause you to lose one or more bands.
We are optimistic about first deliveries at the Friedrichshafen Hamfest in Germany in July 2017. Volume shipping will begin in October of 2017 (due to component lead times and European summer holidays).
Stateside and world-wide availablilty is scheduled for October 2017.
The Aerial-51 will be sold EXCLUSIVELY through Spiderbeam and its world-wide network of resellers. Watch the Spiderbeam web page for availability.
REMEMBER: We at Aerial-51 DO NOT SELL ANYTHING.
We only design unique world-class antennas!
Rick, DJ0IP 19-JUNE-2017
In addition to being erected in its full length, it can also easily be shortened to half-size and erected as a 40m OCFD, covering 7 bands. In that case it looks like this:
Sorry for the fuzzy picture*, but you get the idea. The RMA and outer ~20m of wire are simply removed and left off. It still works on 7 bands, but requires only half as much space as when configured as full-size.
WE BELIEVE this to be unique in the industry.
See the Model 807-L Brochure for more information on this feature.
* I will create a better drawing after the Friedrichshafen Hamfest (2017).
Several 404-UL users have asked for an 80m version of this antenna.
The first "FINAL" prototype has been in the air under test for 3 months now and the first production unit has been built.
It took us 24 months to evolve the 404-L into the 807-UL. We learned several lessons in the process, which I (DJ0IP) plan to one day describe in a book on OCFD antennas.
Unfortunately we just couldn't get the 807 with its remote matching unit light enough to call it an Ultra-Light. Since it is not ultra-light, we added a little more size and weight to the balun and upped it to 500w.
The 807-L was originally 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 also requires a remote matching unit. Therefore it ended up being SIGNIFICANTLY different.
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 3.460 MHz... much lower than anyone would expect . . . or accept.
Obviously we 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. The "RMU" was born.
In the meantime we have developed a method to enable us to set 80m (or 75m) resonance anywhere we desire, without affecting the frequency of resonance on any of the higher bands. In addition, this method has the option of a field upgrade to several other resonant frequencies.
Like the 404-UL, the 807-L is purpose designed for the traveling ham who needs a lightweight antenna, but also needs 80m. Naturally it is also good for home use.
AND OF COURSE IT INCLUDES 15m!
It would not be an Aerial-51 antenna without 15 meters!
Like the 404-UL, the 807-L 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 we 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-L has remained exceptionally low for an antenna covering 7 (8) bands.
The 807-L DOES NOT COME WITH COAX.
It has a standard SO-239 coaxial jack for connecting the coax of your choice. However if you intend to use it with a lightweight telescoping fiberglass mast, DO NOT USE RG-213 OR LMR-400 with it. Instead use any of the lighter coaxes: RG-174 / RG-58 / LMR-240 / Aircell5, etc.
ALL BANDS: "almost" we 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 community of users.
HEIGHT IS MIGHT - PERIOD.
For portable antennas, "lightweight" is key for enabling height.
ESTIMATED COMPLETION DATE:
ESTIMATED AVAILABILITY (Date):
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. On 12m it also looks better than it actually is. The SWR is about 4:1 at the feedpoint, but do to transmission line transformation it is much better with many lengths of coax. It is still very efficient and OK to use on this band.
Now the nitty gritty. The curves below are the final results of my 24 months of development on this antenna. 80m of course may be moved up or down the band as you please. 12m is not quite as good as it looks, but still good enouogh. See paragraph above.
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:
Or if you prefer, we can even move resonance to 3.9 MHz.
Thank you for your interest in my design.