I packed up my portable rig, drove to Hibou Conservation Area and spent about an hour operating by the lake this afternoon. The waves were splashing up onto the shore right in front of me. I only made a couple of contacts; Ted in Delaware and another Ted in New Jersey, both SKCC (Straight Key Century Club) members, but it was a great outing.

Rig: Yaesu FT-891 running 35W, powered by two 7AH Sealed Lead Acid batteries
Antenna: MFJ-1979 telescopic vertical with homebrew loading coil for 40m
Mode: CW - straight key

Beautiful place, beautiful day. I love this hobby!    
John VA3KOT

I wonder if it's possible to persuade an auto tuner to tune ladder line using an external 1:1 current balun

https://www.balundesigns.com/blog/baluns...dder-line/

http://www.kk5jy.net/LoG/?fbclid=IwAR19Q...zodq7a9tH4

The End Fed Half Wave (EFHW) antenna is very popular for portable use. It is a very simple antenna that is easy to erect, very lightweight and easy to carry during pedestrian mobile operations. I use one for my /pm ops and have set it up in several provincial park campgrounds. I also use an EFHW at my home QTH. It does not require a counterpoise or radials because the very high feedpoint impedance results in very small common mode currents that are easily dissipated in a few feet of coax or a good ground stake at the feedpoint.

There are a couple of challenges that have to be overcome. The first is the very high feedpoint impedance. That impedance can be several thousand ohms. In order to match it to a 50 ohm coax a 49:1 or sometimes 64:1 toroidal transformer is needed. Fortunately, it is very easy to build such a transformer using a type 43 ferrite toroid (I order FT240-43 cores from Mouser Electronics in Kitchener, Ontario) with either a 14:2 or 16:2 turns ratio.

The second issue is that a half-wave on 80m is 132ft long and may not fit in the available space. Provincial park campsites are typically much shorter than that. This problem is compounded by the need to run the coax at 90 degrees away from the feed point (otherwise a return current is induced in the coax braid). A solution is to shorten the antenna using a coil part way along the wire. But, how much inductance is needed and by how much can we shorten the wire?

I worked out a simple answer to that question. An EFHW antenna also works on harmonics of its fundamental frequency. I built mine for 80m (for the club net Wednesday evenings on 3783KHz) but I also use it on 40m and 20m. The length of a quarter wave antenna on 80m is 66 feet which is also a full wavelength on 20m and a half wave on 40m. If we place our coil at 66 feet from the feed point the rest of the antenna must then be electrically equivalent to another quarter wave on 80m.

Now we can simply use an online calculator to determine the inductance of the coil for any desired length of wire (L2 in the accompanying diagram). There are several sites available that will calculate the inductance for either a loaded dipole or a loaded quarter-wave vertical antenna. I found it was necessary to trim the antenna length for resonance in the part of the band required. Beware, a loaded antenna has a high Q which means pruning must be done in small increments. It also means the bandwidth is narrow and a tuner must be used outside the design frequency range.

My 80m EFHW antenna for camping and general portable use is only 75 feet long with a coil of 113 microhenries. Compare that with a full size 80m EFHW at 132 feet long! It actually fits into an even smaller space by erecting it as a sloper or inverted-V antenna. At home I have a little more space available so I use a coil of 37 microhenries for an overall length of about 86 feet.

By the way, it helps to have an inductance meter to directly measure coils. I wind my coils on random pieces of scrap plastic tube and determine the required number of turns by intelligent guesswork and trial and error!

John, VA3KOT    

The conventional wisdom is: "get your antenna up as high as you can". But, as Mike Toia K3MT has demonstrated and published, a wire antenna laid directly on the ground also works. Mike calls his antenna a "Grasswire". Critics dismissed the idea as ridiculous. Ground losses will completely wipe out your signal, they say. But anyone who has tried a Grasswire (many, including myself) knows, it does work, with some limitations. Here is how it works.

The signal in the antenna will induce a reflection in the ground. The reflected wave in the ground exactly cancels the signal in the antenna - up to about a half-wavelength. Because the reflected wave travels more slowly than the above ground signal, the phase relationship between the two changes with antenna length. If the antenna is at least a full wavelength long, less of the signal is cancelled by the reflected wave. At some point, the phase relationship results in zero cancellation and the signal is radiated as though no ground is present (see attached diagram).

K3MT measured the current in the antenna wire along its length and determined that the current (and therefore the radiated power; remember P=i^2R) diminishes rapidly and that any antenna over one wavelength long is unnecessary. In contrast, the US Marine Corps used very long wires (5 wavelengths) for field expedient antennas in Vietnam, but they kept the wire at least 1 metre above ground, thereby reducing ground losses.

A very long wire (aka Wave Antenna) radiates a vertically polarized signal off its ends. At a certain angle between the incident wave and the ground (known as Brewster's Angle) the signal is reflected instead of being refracted into the ground. You can observe Brewster's Angle by going to the Huron coast in the evening and watching the sun get lower in the sky. At a certain height above the horizon the sunlight will reflect brightly off the surface of the lake. This is the effect that takes place with a Grasswire Antenna.

I have experimented with Grasswires for several years with limited success. My devotion to QRP ended with the poor propagation conditions accompanying the latest solar minimum. According to EZNEC, a Grasswire will result in a gain of about -12dB. A 5 watt signal will be attenuated down to milliwatt level but a 100 watt signal into a Grasswire will still radiate 12.5 watts.

So why use a lossy antenna? Stealth! A Grasswire is invisible. Lay it down anywhere and operate. It can be deployed in seconds and you're on the air. And fun. I enjoy the experimental side of ham radio.

Here are my results from today's test (interrupted by rain before I could get a QSO so I tried WSPR):        

https://www.facebook.com/United-Nations-Amateur-Radio-Club-4U1UN-169357566427247/




Greetings from UNARC/4U1UN. As most are aware, UNHQ has been shut down for some time due to COVID-19. As a result, basic maintenance of equipment has been postponed until the building is reopened to staff. The Secretary General has implemented a multi-phased approach based on state and federal guidelines. As such, we hope to regain access in October or November. It's at that time that maintenance activities will be scheduled with the appropriate departments in order to address pressing equipment failures. This includes repair to our Acom amplifier control module as well as the beacon antenna.



On other news, I've been testing and evaluating a Flex Radio Systems 6600M which was kindly loaned to us by our friends at Flex Radio. The Flex SDR system has proven more than capable of performing in our constrained operating environment, and is something as current club president, hope to implement into our station as soon as possible. Many thanks go to Flex Radio, especially, Matt Youngblood for his generosity and willingness to work with the United Nations Amateur Radio Club 4U1UN.



I'll try to update you with more news as it's made available to me by senior management and our administration.



Until then, be safe. Be well.



73,



James K2QI

Found this on the ARRL website:
73, Dave VE3WI

AMSAT-DL Submits Lunar Lander Proposal to European Space Agency
07/13/2020
Germany’s amateur satellite organization AMSAT-DL has submitted a comprehensive proposal to the European Space Agency (ESA) for its Lunar Amateur Radio Transponder (LunART) lunar lander — a communications platform on the Large European Lander to support communication and payload experiments. AMSAT-DL’s Peter Gülzow, DB2OS, and Matthias Bopp, DD1US, say that a LunART (called “LunaART” in the AMSAT-DL proposal) would support direct communication with Earth via amateur radio, support university and student payloads and offer direct access to their experiments, and expand the reach of radio science. It could also provide backup communication capability and capacity during an emergency, or when the ESA network is busy.

The comprehensive radio platform would use the European frequency protocol of 2.4 GHz up and 10.45 GHz down (approximately 100 W), pioneered in the QO-100 satellite, the first geosynchronous amateur radio payload. The platform would also include a VHF/UHF transponder. AMSAT-DL would develop and build the necessary hardware and software and provide ground station support via the 20-meter dish at AMSAT-DL headquarters in Bochum, Germany. They envision developing a smaller ground station with an approximately 1-meter dish to support groups, including schools and universities. Low-power beacons would transmit on various frequencies from VHF (145 MHz) through SHF (up to 24 GHz or even 47 GHz), AMSAT-DL’s proposal says.

“This transponder would also be an ideal platform to develop new transmission schemes with novel modulation and coding techniques optimized for long-distance communications with the corresponding high latency (long delays),” AMSAT-DL said. “This would provide essential knowledge in preparation of a future Mars mission.” In addition, LunART could include the capability to transmit still or slow-scan television images and video to schools “from cameras attached to the lander monitoring the moon surface and perhaps the Earth in the background [which] would be ideal stimuli for getting school kids and STEM organizations further interested in space.”

The proposal is on open access at the ESA website and is now being evaluated. AMSAT-DL’s LunART follows the Lunar Amateur Radio Interaction Experiment (LARIE) proposal from Andy Thomas, G0SFJ. Both refer to weak signal modes and suggest the same frequency bands. Thomas said he welcomes LunART as a well-developed proposal and hopes ESA will support it as well. — Thanks to Southgate Amateur Radio News, AMSAT-DL, and ESA

Searching for info on Cabot Head, I found this:

https://www.owensoundsuntimes.com/news/l...lar-refurb

I particularly like the bit about the folks who built houses at Dyers Bay along the road and now are complaining about the traffic (duh!)

Future looks uncertain to say the least.  Road needs expensive repair & lighthouse has serious water damage.  Municipality obviously wants the Feds to pay it all.  It would be a shame to lose it after DFO just spent 1.3 M$ of our tax money to "make it safe".

I enjoyed doing ILLW up there, be a real shame if we can't operate there any more.

73
Dave, VE3WI

My Contacts.
At the camp I had the radio steaming for a few hours of operating, this was the most I operated on FD in a long time. I used my Kenwood TS 440 with 3 home made wire antennas strung in the trees, one was for 80, one 40 and one 20. I actually strung up 2 different wires for 40 but one did not match up because it got stuck up in branches.

80, 21 contacts
40, 58 contacts
20, 7 contacts

Well,  It was fun,    but somewhat fewer Q,s  than I had hoped for...     Spent a lot of time looking for new section/mults rather than
max Q's...     80M    33 CW,    4 digi    37 
                     40M    25 CW,  16 digi    41                                 (   51 sections,   37 states,     4 countries..   )
                     20M    52 CW,    6 digi    58
                     15M      7 CW,                  7                   
                                          Total  HF   143
                                    Satellite  (SSB)     2
                                                     -----------
                                                            145.......

Had a bug in the system when I fired up this morning !!    It appeared at first I had a major SWR problem  with the 40M antenna..
Wasted nearly an hour inspecting  and testing,,  eventually finding an  earwig jamming the meter movement inside the SWR bridge...

Now ,  on to the log filing...........................................................