Field Deployment Of Antennas
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Field Day provides great practice setting up antennas "on the fly" somewhere other than on home turf. However, it is a planned activity, and the event venue is often the same one, two, or few places. As a result, setting up becomes almost a reflex action in some cases. Good practice, and well worth the effort, but we often don't need to consider things like we did the first time or two we setup somewhere.
Things we have to consider when setting up at an unknown location include site selection and safety, the most efficient means of getting up and operating, propagation and proper antenna orientation, optimizing the installation, and the need to avoid some pitfalls related to setting up "on the fly".
When arriving at a new location we need to consider takeoff angles for HF and line-of-site for VHF/UHF,
P.A.C.E. and EMCOMM
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The military, various government entities, and some NGOs, plan for emergencies by implementing a multi-layered plan. Essentially, four "independent" levels, each one more reliable and less reliant on infrastructure than the one before it. As you might imagine, each letter represents one of the levels: P(rimary), A(lternate), C(ontingency), and E(mergency). I suspect you can guess which layer we fall into!
For PACE to function all players must roll through the levels in order, from P to A, A to C, and C to E. As we often say, Amateur Radio: When all else fails!
While each layer is to be independent of the resources of the preceding one, it is not always the case. Obviously, the more self-contained each system is, the more likely it is to function despite other failures.
HOAs, Amateur Radio, & EMCOMM
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Amateur Radio Operators and HOAs go together like oil and vinegar in most cases. Rules regarding antennas or "other structures" on a property bound by HOA rules often makes installation of HF antennas impossible, and even makes VHF/UHF installations challenging and less-than-optimal.
The FCC has addressed local ordinances with PRB-1, which legally inhibits local governments from imposing unreasonable limitations on radio operators. Our ability to provide emergency communications support is at the core of the argument made for PRB-1 freedoms. Sadly, PRB-1 does not impact HOAs because the HOA rules are imposed by private contract, not legal ordinances.
NVIS Antenna Configurations
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NVIS (Near Incidence Vertical Skywave) is best accomplished transmitting in the most common NVIS bands (80, 60, ad 20m) with a very high angle of incidence, the radio waves going almost straight up. This is the exact opposite of what we are doing when we're "DXing" (distant communications); as a result, almost all the logic we apply to setting up antennas is turned on its head. We must utilized antennas in ways we typically would avoid, and we'll cover the different ways here. The key is to remember we are attempting to direct radio waves upwards, rather than towards the horizon.
Dipole Antennas
These are the most common antennas in amateur radio. They are easy to make and work well. For DX, all you need to do is get them as high off the ground as you can get so the bulk of the radio signals are radiated towards the horizon.
QRP, NVIS, and 60 meters in EMCOMM
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Low Power (QRP), Near Incidence Vertical Skywave (NVIS), and the 60 meter band looks more and more to be intended for use in Emergency Communications (EMCOMM). I've touched on all of this over the last few presentations, so all I'm really doing here is putting it together.
The recent changes to the 60 meter band embrace the use of QRP on that band. What was the third channelized frequency in the 60 meter band has been eliminated, the frequency spectrum in consumed, and the adjacent portions of the band between the 2nd and 4th channels is now VFO tunable - with the caveat that operation must be QRP (9.15W ERP). The remaining channelized frequencies may still operate at the previous 100W (ERP) level.
The New 60 Meter Band
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Recent NVIS tests we conducted showed, at least for early daytime hours, 40 meters worked best for NVIS, although both 10 and 20 meters did perform, just not as well as 40 meters. As one might expect, 80 meters did not work well in daytime for NVIS.
Some of us discussed 60 meters, the channelized band, as a possible NVIS candidate. An indication it might perform well is the fact the Federal Government uses it as part of their emergency communications system and SHARES, a public/private emergency communications network.
During those discussions we considered executing a NVIS exercise that included 60 meters. Coincidentally, the FCC has made changes to the 60 meter band, eliminating one of the channels and replacing it
Antenna Polarization
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Our recent NVIS (Near Incidence Vertical Skywave) experiments brought to light a discussion of antenna polarization. Does it matter? Does it impact NVIS? Absolutely and absolutely.
First, lets talk about polarization on VHF. We all generally run vertical antennas when running VHF-FM. It works well when reaching out to repeaters or attempting point-to-point simplex communications. However, if two operators are attempting to communicate VHF-FM and one is horizontal and one is vertical, they will have issues. The E-fields are oriented perpendicular ("cross-ways", so to speak), and the loss of 10db-20db, signal degradation to 1/10th to 1/100th, is the result. It's just the nature of how radio signals are picked up by the antenna. In this case, compatible orientation is vital.
Know Your Gear
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We discussed standardizing channels in a previous ARES net (and also at a recent WGARS meeting). Why? Consistency makes for an easier time dealing with unusual circumstances; not having to spend time and mental effort finding the right channel.
Even more important is to understand how to operate the radio. Here are a few items to be sure you know how to do:
Power
Obviously the most important thing to know how to do.
The Display
Do you know what all those little symbols on the display mean? At least the important ones? It's a good first step to figuring out why the radio isn't operating as expected. You can see what functions are turned on or off, like memory or VFO, tone, offset, annoying roger-beeps, etc. and from there know what you may need to do to resolve an issue.
Amateur Radio, ARES, and RACES
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In previous ARES presentations I have made reference to other entities that either provide Emergency Communications services, or need the ability to utilize them during an emergency.
While we focus on the Amateur Radio Emergency Service (ARES), sponsored by the ARRL, for providing emergency communications, the only entity recognized formally in FCC regulations is the Radio Amateur Civil Emergency Service (RACES). So what is RACES, and why do we hear so little about it?
RACES is recognized in FCC regulations Part 97, Section 407. RACES is a service comprised of Amateur Radio operators who report directly to a Civil Defense Agency like FEMA, GEMA, and local
QRP And Amateur Radio
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While many operators tend to operate using the 100W or 200W their radio provides, and yet others use external amplifiers to run hundreds, even more than 1KW, there are others who operate at the other end of the spectrum, 5-10 Watts.
QRP operation is often practiced by operators participating in Parks On The Air (POTA) or Summits On The Air (SOTA), who are often hiking or backpacking their equipment to the operating location, carrying their power source with them. Naturally, packing a Marine Battery would be a bit of a challenge, so smaller and lighter batteries with lower power capacity are used.
Due to limitations in available power the operators naturally run less power, usually 20W or less. QRP is generally considered 5-10W, but even 20W is possible with more efficient modern equipment and Lithium batteries.
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