Inverted-V / Dipole
+30m with reduced power
Power (807-L / 807-HD):
600 Watts SSB/CW
150 Watts on 30m
Physical (807-L / 807-HD):
Length: 40.7/40.8m (133'/134')
Weight: 490g / 850g
(14oz. / 28 oz.)
Pictured Here: 807-L --> -->
See Also: 807- 'HD', 'HP', 'L', 'LP', 'UL' in the menu on the left.
DOWNLOAD MANUAL: PRELIMINARY USER MANUAL (for 807-L & 807-HD)
DOWNLOAD BROCHURE: MODEL 807-xx BROCHURE (for 807-L & 807-HD)
DOWNLOAD TECHNICAL INFO: MODEL 807-xx Technical Info (for -L & -HD)
The 807-L was the first 80m product out of the chute (Q3-2017), and the 807-HD became available in Q2-2018.
The new 807-L (2018) is identical to the original 807-L, but now 300 grams lighter! It has the same purpose-designed "Hybrid Balun"...with power handling of:
The total weight is now about 425 grams (14 oz.) just 25 g (peanuts) more than the originally 40m OCFD antenna.
The '807-L' uses the same stealthy thin wire as used in the Ultra-Light "UL" 40m version. When hung from a tree at 12m (40') height, nosey neighbors can hardly see the antenna!
The 807-HD (weight 800 grams) uses thicker, stronger wire. Though somewhat thicker, it is still barely visible to the neighbors.
Additional 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 33g (~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 (approximately) to :
THE FREQUENCIES STATED ABOVE ARE ONLY BALLPARK NUMBERS
(Resonance varies slightly from one QTH to the next.)
CHOICE OF RMU: Beginning in the second half of 2019, buyers will have a choice of which RMU they want. Currently there is a world wide short supply of the power-SMD capacitors used in the RMU. That was the cause of the delay.
Earlier shipment units are resonant about 3.680 MHz.
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NOTE: Unlike normal dipole antennas, you CANNOT adjust resonance simply by changing the length of the antenna legs. This will likely cause you to lose one or more bands.
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Both versions have been shipping for 2 years now.
For the current status, see: CURRENT AVAILABILITY.
Aerial-51 Antennas are sold EXCLUSIVELY through Spiderbeam and its world-wide network of resellers. Watch the Spiderbeam web page for availability of different models.
REMEMBER: We at Aerial-51 DO NOT SELL ANYTHING.
We only design unique world-class antennas!
Rick, DJ0IP June-2019
In addition to being erected in its full length, all 807-xx antennas can easily be shortened to half-size and erected as a 40m OCFD, still covering 7 bands.
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-xx Brochure for more information on this feature.
Several 404-UL users asked for an 80m version of this antenna. 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 600w. We also made it available in a Portable Version (abt. 490g) and a Heavy Duty Version (abt. 800g).
The 807-L/HD and 404-UL are based on a concept proposed by Karl Hille, DL1VU (SK), known as "Current-Sum-Antenna". They are fed off-center, but at a different position than that of traditional OCFD antennas.
The 807-xx family of antennas is roughly twice as long as the original 404-UL antenna. They have a new unique, purpose-designed balun which better addresses the common mode current characteristics of the 80m version of this antenna. It also requires a remote matching unit. Therefore it ended up being SIGNIFICANTLY different from the 404-UL.
In order to have higher bands in resonance, it was necessary to set the 80m resonance low, very low; well 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, but in the interest of longevity, the 807-HD is the preferred version for permanent installations.
AND OF COURSE ALL 807-xx MODELS INCLUDE 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 (the RMU) to achieve all of the design goals.
I'm sure many people are curious to learn how we did this, but I'm afraid I must disapoint you; we are 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 8 bands (actually 9 bands with tuner).
The 807-L and 807-HD DO NOT COME WITH COAX.
They both have a standard SO-239 coaxial jack for connecting the coax of your choice. However if you intend to use them with a lightweight telescoping fiberglass mast, DO NOT USE RG-213 OR LMR-400. 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 without the help of a tuner [yet]. We have not even looked into 60m coverage.
HEIGHT IS MIGHT - PERIOD.
For portable antennas, "lightweight" is key for enabling height.
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 great antenna for 30m, but it still works fine on this band with a tuner (max. 150W). On 12m it also looks better than it actually is. The SWR is about 4:1 at the feedpoint, but due to transmission line transformation it is much better with different lengths of coax. It is still very efficient and OK to use on this band, though depending on length of coax, you may wish to use a tuner.
Now the nitty gritty.
The curves below are the final results of my 24 months of development on this antenna. The values shown are typical for ALL 807-xx versions. 80m resonance may be moved up or down the band as you please, by changing the RMU. 12m is not quite as good as it looks, but still good enough. 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 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 looks like with the Region 2 RMU:
Or if you prefer, we can even move resonance to about 3.9 MHz, by using the RMU-75.
Thank you for your interest in our design.
The Aerial-51 Team,
Rick, DJ0IP & Sebastian, DO5PNS