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WF7A
09-07-2008, 06:07 AM
Howdy, all:

I've been asked to submit a three-part article for an ultralight pilot magazine about radios and thought I'd best get your opinions to see if it's near the mark or not. I've included the rough draft below so I'd really appreciate your input. Remember, these guys aren't radio savvy so I have to keep things simple.

Thanks!
Rich

pee ess: Some of the formatting was lost when I dumped the text in here from MS-Word. Sorry!
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While taking some PPG flight training recently, I had the opportunity to use what many PPC and PPG pilots use for communication between other pilots in the air and on the ground, FRS radio transceivers. I quickly came to the conclusion after a few radio exchanges with my instructor that although FRS radios are inexpensive and easy to use, they…well…suck: They have very limited range and are prone to interference from other FRS radio users and PPG electrical systems. With radios being such a critical link to flight safety and for flying with our buddies, it’s amazing how little pilots know about them. What this series of articles will do is not only educate you with a little radio theory, radio choices and usage, but also how to build simple yet very effective antennas for both air and ground use to extend your radio’s range well beyond what you’re used to…which can save your skin some day when the chips—and you—are down!

Radios 101

“I tell ya, I get no respect, not even from my parents. When I was a child they gave me one walkie-talkie as a birthday present.” —Rodney Dangerfield
Simply put, a radio transceiver’s job is two-fold: to convert sound waves (or digital data) into radio waves and back again. But when you think about it, your radio is really two systems: the radio transceiver itself and its antenna. Let’s talk about the radio, first.

The radios we typically use are either channel-specific or operate over a range—or band—of frequencies…but which channel or band should we use? The easy answer is “That depends.” If you want to communicate with other general aviation pilots then an aviation band (“avband”) radio is the best choice; CB users, a CB transceiver; amateur radio (“ham”) operators, HF, VHF, and/or UHF radios, and of course the ubiquitous FRS radios. The real question is, “Which one would be best?”
Again, that depends.
If you never plan to chat with general aviation aircraft or controls towers then you obviously don’t need an avband radio; CB radios are notoriously subject to interference, both natural and man-made, and require long antennas to get any distance with them. That leaves ham radio transceivers, with a 2-meter VHF model your best bet. Here’s why:
·affordability: a basic 2-meter radio, sans unnecessary bells and whistles, costs around $150 for either a handheld one or a mobile one for a vehicle or base station use;
·access to repeaters: Repeaters dramatically extend the range of a radio, especially from the ground, by rebroadcasting your signals over a great distance—a BIG plus if you’re down somewhere that’s ringed by mountains or hills that block radio waves;
·ease of use: You’ll need to obtain an amateur radio license to use the radios but it’s easy to get one: no Morse code knowledge is required and the Theory test is a simple multiple-choice exam. You’ll need to learn a little elementary radio theory and good operating practices, but it’s relatively easy stuff;
·lots of accessories are available, and
·a support network: Hams are dedicated to public service so if you need help because you’re hurt or stranded somewhere, a fellow ham will be happy to help you out.

If there’s any “con” to using a ham radio it’s that you have to ID with your callsign every ten minutes while engaged in a conversation, and when you initiate and end a conversation—a minor inconvenience at most. To learn more about obtaining a ham radio license, go to www.arrl.org (http://www.arrl.org/) or www.fcc.gov (http://www.fcc.gov/). For which model radios are winners or losers, check out the radio review sections submitted by ham radio operators at www.eham.com (http://www.eham.com/) and www.qrz.com (http://www.qrz.com/).

Antennas 101

Antennas are probably the least understood component of a radio system—you just take it for granted it does its thing by collecting or broadcasting radio waves, which it does, but depending on its construction it can either be very efficient or just a shade above useless. Assuming a good conductor is being used—e.g., aluminum, copper, steel, or brass—in its construction, a key factor in determining antenna performance is how long it is so we need to determine that, first; it’s based on a radio frequency’s wavelength.
As an analogy, a radio wave is like an ocean wave in that it has crests (peaks) and troughs and that there’s a distance (wavelength) between one crest of one wave and the next. (See Figure 1.) Like the Speed ¸ Time = Distance formula we use for flying, we use the same formula for determining wavelength, or the Distance part of the aforementioned equation, by substituting Time with Frequency.
In free space, radio waves travel at the speed of light (approximately 300 million meters per second). So, there’s our speed. Next, we need the waves’ frequency, or how many times (cycles) it repeats itself in one second, by convention called Hertz (Hz). For example, the FRS radio frequency range is from 462.5625 MHz (Channel 1) to 467.7125 MHz (Channel 14); that means for Channel 1 there are 462,562,500 cycles per second and Channel 14, 467,712,500. (The “M” in MHz means “multiply by 1 million.”)
Let’s take the middle of the frequency road[1] (http://forums.qrz.com/#_ftn1), FRS Channel 7 (462.7125 MHz), and find its wavelength. After canceling like values in the fractions (millions), the calculation can be reduced to 300 ¸ 462.7125 = 0.648 m (25.5 in.); if you were to cut a piece of wire that long it would represent its physical and electrical wavelength.[2] (http://forums.qrz.com/#_ftn2) In real world antenna design, the wire, or conductor, can be longer or shorter than its electrical wavelength; generally, an antenna physically longer than its electrical wavelength is more effective a radio wave radiator/collector; shorter is less effective.
Without getting technical here, you can discard half of a full wavelength antenna yet still have an efficient radiator half a wavelength long, so let’s cut our full-wavelength antenna in half from the previous example, leaving us with 32.4 cm (12.75 in.) It doesn’t take a genius to see that the antenna on all U.S.A. FRS radios isn’t 12.75 in long. So, what gives? Can’t the manufacturer’s antenna engineers perform simple math? Are the manufacturers so cheap that they’re short-changing us in wire?
There are a couple of reasons why an FRS antenna is so short and fixed in place:
·the FCC (Federal Communications Commission) wanted to limit an FRS radio’s range—that’s why you can’t buy a longer antenna for them. A shorter antenna means reduced range, and
·ergonomics: It would be all too easy to break a longer antenna through carelessness.
However, there’s a not-so-obvious result of an antenna being shortened well below its electrical wavelength: you’re going to take a big hit in antenna efficiency. How much? I’m glad you’re sitting down. The FRS antenna is only about 4 cm (1.5 in.) long. With a paltry maximum 500 mW to begin with (that’s half of one Watt, about 1/8th the power of a common bathroom nightlight), its typical antenna efficiency is about 1%–10%, or 5 mW–50 mW. In practical usage, that means about half a mile range in open land or as little as 100 yards indoors…and that’s if you’re lucky.[3] (http://forums.qrz.com/#_ftn3) FRS radios don’t look so attractive now, do they?
Let’s examine the 2-meter ham radio: it has a frequency range of 144 MHz–148 MHz. Taking the middle-of-the-road 146 MHz, its wavelength is 2.05 meters (hence a “2-meter” radio), or 6.7 feet. (In comparison, an avband radio—which has a usable (voice-only) frequency range of 118 MHz -136 MHz, or a center frequency of 127 MHz, is a little longer: 2.36 meters, or 7.75 feet.) Aside from having an average of 5W[4] (http://forums.qrz.com/#_ftn4) power available, you now have many antenna options available to you that you didn’t have with the FRS radios. To find out what they are, you’ll need to read Part 2 of this article in the next issue. :)

[1] (http://forums.qrz.com/#_ftnref1) It’s standard practice to design an antenna for the middle of the frequency range of its intended use; that’s because as you transmit or receive above or below its designed, or resonant, frequency, its performance begins to suffer.

[2] (http://forums.qrz.com/#_ftnref2) Just for fun: The wavelength of a 60 Hz signal coming out of an electrical outlet in your home is 5,000,000 meters, or 3,109 statute miles between peaks; that’s Seattle to Tampa in one second! In contrast, a GigaHertz—a common unit used in computer microprocessor speed—is one billion cycles per second; if you want to see how long its wavelength is, cut a wire 30 cm (11.8 in.) long.

[3] (http://forums.qrz.com/#_ftnref3) When you see something like “26-mile range!” on an FRS radio’s packaging, that’s the theoretical range based on mathematics, not an empirical measurement.

[4] (http://forums.qrz.com/#_ftnref4) Although 5W is ten times more powerful than the FRS’s 50mW, it doesn’t automatically mean it has a range ten times further; radiated energy is a function of logarithmic power increases, not exponential.

KC7JTY
09-07-2008, 06:11 AM
Can I stop by and have you read it to me?

WF7A
09-07-2008, 06:37 AM
It's 11:36 pm--you want a ham bedtime story? :)

I'm a terrible reader: I stammer a lot, slur words...which explains why I prefer CW as my mode of choice.

I used Dragon Naturally Speaking on my computer but it kept repeating words on me. :S

KD6WAG
09-07-2008, 06:58 AM
Article looks good, but I'd just be worried about two specific issues here. 1st is that a very few "some" pilots would disregard on getting a ham license all together and talk on the 2m ham bands illegally. 2nd is a safety issue. That being not being able to communicate with OTHER aircraft. Yes you're an ultralight pilot. As you know, that restricts you as to where YOU can fly your aircraft. However, is DOES NOT restrict other airplanes and helicopters from flying within the airspace that you are operating in. What does all this translate to: It means that IF some other aircraft needs to communicate with you, he/she can't. Because the chances are the other aircraft DO NOT have ham radios with them. They have "Nav-Com" aviation radios.

My personal opinion is this: You rewrite the aritcle and tell the guys to buy a hand held "aviation" radio. ICOM makes several great ones. Next, you write in your article about the only two FCC designated air-to-air public use frequencies for ALL aviators within the U.S., those being:122.75 and 122.85 That would be your best bet.

Why? You ask, good question. Because now your pilots have a designated air-to-air commumication capability with thier "aviation radios" AND most importantly.... If they need to talk to ATC (towers etc...) or put out a position report in an uncontrolled air strip within the Class G airspace, they have a radio that fits the bill!!!! Other aircraft can hear and communicate with the ultralight pilots. Now, EVERYBODY is safer.

A ham radio can't (legally) transmit on those two above aviation air-to-air frequencies. Look at it this way. While you ultralight pilots are flying and talking to each other, what if a helicopter or other low flying aircraft needs to communicate with the ultralight pilot for some reason? It's very well possible, especially with low flying helicopters like fire/police etc... 99.999% of all aviators have 122.75 and 122.85 capabilites. They DON'T have ham frequencies. Let alone the fact that most aviators wouldn't know which ham frequency you're actually communicating on. If the other aviators happen to see you flying and need to get in close or land, or put out a position report, they're probably going to try the nearest CTAF freq to communicate with YOU. If the ultralight pilot doesn't answer on the CTAF for that area, the next frequency the other pilot is going to try is one of the two air-to-air freq's listed above. It's all about functionality for you guys and your great sport with SAFETY for all aviators. That's why those two frequencies were created and designated for ALL pilots, regardless of type/class.

I think that ham radio should not be used for "regular" air to air purposes for above mentioned safety reasons. One should use an aviation radio with the desiganted air-to-air frequencies AND..... other aircraft frequency capability. When flying close to other ultra lights, why would you even need a repeater? You should be on a simplex frequency anyway and 122.75 & 122.85 are simplex aviation frequencies outside of the ham bands. Less interference to other hams, unless you specifically want to talk to hams while flying. That's different then. I wouldn't do it unless I could also monitor aviation frequencies. Myself, I'll talk on ham radio while flying, but I have my aviation radios on too! It's safer that way.

Last point, (and I say this in a friendly way, please don't take offense) if you're still "hell-bent" against using an aviation radio for whatever reason, how about using GMRS radios? Unlike FRS which is limited to a 1/2watt of power, a GMRS is 5 watts. More than PLENTY of "punch" for air-to-air communications for fellow ultra light pilots. The only down side is that you still need a license for them, but.... you don't need to take a test if I recall correctly. I believe that you also don't need to identify every 10 minutes, but I may be wrong on that belief. But who cares about identifying, it's no big deal. GMRS radios would be alot cheaper than ham radio too. Why would you need a repeater for air-to-air communications with your fellow ultra light buddies? Maybe I missed something in your article.

This is just my opinion based on being a ham radio operator AND a low flying commerical pilot. I think I can voice my opinon on both fields based on first hand daily experience. On occassion, I've run across a few ultra light pilots in the desert areas. I was only thankful that they were smart and had a handheld aviation radio to communicate with. A few times they had nothing and although nothing bad came about, there is always "what if?" It's better to have and not need, than to need and not have. That's my philosophy when it comes to flying and communications capabilities.

Remember, aviation hand held are nice and reasonably priced. About the same as a good quality hand held ham radio. Go to ICOM's web site. You can even buy accessories for them like lapel mikes for virtually hands free operation (or limited hand operation). You can even use quality light weight aviation headsets with ear/mic addapters plugged into the aviation radios. I have one myself! You can buy larger capacity batteries just like for ham hand held radios etc.... There are many many more options available.

I would really look into this before you publish your nice article. I know you worked hard on it but again, there is a reason why the FCC and FAA designated an air-to-air communication system on the VHF AIRCRAFT ("2.4Meter") band.

I guess you could always tell the pilots to carry two radios. Ham and aviation, but you guys usually want to limit weight if possible. I'd stick with the aviation radios for common sense reasons.

AE4TR
09-07-2008, 10:30 AM
:o

Pretty dry reading, you might want to add a little humor to it and make it more interesting.. I submit the following for your consideration.






PROCRASTINATION
AN ODE TO HAM RADIO

While sitting in my shack one night,
Looking out the window, what a beautiful sight.
The sun had set, the moon was shining bright,
Every thing was fine, much to my delight.

Listening to my radio, the hams were complaining,
There's a storm brewing, static was increasing.
As I watched the moon, much to my dismay,
A cloud passed over, more was on the way.

Soon there were many, the moon began to dim,
The temperature was falling, winter was setting in.
Rain was now falling, and snow began mixing,
I just remembered, "MY ANTENNA NEEDS A FIXING".

It had served me faithfully for so many years,
I should be ashamed, it almost moved me to tears.
Work while the sun shines, my father told me,
But I was lazy, and time passed, as you can see.

Fear not, it's still up there, I said, as gladly I went to bed,
It's battered and torn, and hanging by a thread.
It's winter outside, and dark as can be,
It will make it through the night, just wait and see.

The next day came, I was up early waiting for daylight,
I went to my shack, in snow , up to my back.
It had snowed all night, now Ice was forming,
I slowly drank my coffee, while waiting for morning.

I turned on my Rig, a-hah! I said in my head,
It's still working, or else all would be dead.
The hams were still complaining and going strong,
There's snow and ice, and it will be here for long.

I rushed outside to have a look see,
But more damage to my antenna was not seen to be.
It's still up there, I said, while my feelings were a mixing,
There's one thing for sure, "MY ANTENNA STILL NEEDS A FIXING".

By: Bennie H Mineer AE4TR
South Shore, KY.


This ought to make your article complete, or maybe even destroy it!

Have a good day anyway.

:)

WA0LYK
09-07-2008, 01:05 PM
Let me throw my two cents in here. I know you're focus is on distance and power and the benefits amateur radio can provide with these two factors. I understand you may want good communications if you happen to land somewhere away from others so you can be picked up.

But something you also need to focus on is environmental factors. FRS radios, while cheap, have been designed with some factor of physical abuse. This factor is probably higher than most ham handhelds. Now I have no experience with this hobby so I'm not sure what vibrations, accelerations, etc. a radio is subjected to. I do know on a motorcycle a lot of amateur handhelds do not last a long time if permanently mounted. They even experience problems if you keep them on your belt. The vibration just ends up shaking them until things come loose.

I would expect aviation radios (and/or many commercial radios) to have much more resistance to vibration but I might be wrong. In any event looking for any inexpensive radio that lasts a long time in an environment with constant vibration is probably not the most economic thing to do.

In the end, if you're going to do a professional job of recommending what radio and what bands, please examine more factors than just power and distance. Safety has already been pointed out and I have mentioned environmental conditions. I would probably also do a cost benefit of some kind. You may end up recommending more expensive radios (like commercial) but have a lower cost of ownership over time.

Perhaps even a full seasons test evaluation with an amateur radio by you or a small number of folks in your group would give some valuable information as to ergonomics, equipment failures, etc.

Jim
WA0LYK

K7MH
09-07-2008, 03:36 PM
I'll wait for the movie.

K8JD
09-07-2008, 04:01 PM
Many years ago the shop I worked for had a customer that used hot air balooning as part of thier Ad and promotion business. We supplied hand held and mobile VHF radios, they were licensed under the land-mobile rules and used an itenerant VHF FM. frequency because they worked in different areas and had no "fixed" base radio. This system was for comms between thier mobile radios in "chase" vehicles and the baloons where a handheld radio was used. What other provisions they used, if any, for Avation comms I am not sure of.

W5HTW
09-07-2008, 04:21 PM
My first response is "Ah ha! more folks with ham tickets who aren't the slightest bit interested in ham radio, and who, by the author's admission, know nothing about radio."

Come to think of it, that's also my second response.

My third response is what WAG said. You're in the air with other folks and some of them may not be flying with the same restrictions you have. An ultra light coming up under the belly of a C172 probably isn't exactly a pretty sight.

Don't know about now, but back when I was actively flying I once made an approach to an airstrip and nearly got busted, though I was using standard radio procedures. Problem is, the crop duster also approaching the strip, just around dark, didn't have an aviation radio, only a business band radio. Coming up beneath me, he spotted me kind of late in the game and made a sharp turn. I never knew he was there until he buzzed by my left wing tip, his only light a small strobe.

Nah, I'd recommend aviation hand held radios for this activity.

My fourth response is identical to my first.

WF7A
09-07-2008, 05:30 PM
Great responses and input, guys--thanks! In response to a few of your suggestions:

Vibration isn't a consideration with handheld radios since 99.99% of PPG and PPC (Powered ParaGliding and Powered ParaChute, respectively) pilots wear their radio on their person. Also, weight isn't a factor since wearing a handheld wouldn't affect weight-and-balance and density altitude-related issues (although some pilots are dense at any altitude, but I digress). If the radio's added weight would cause a go/no-go condition of flight then you _really_ shouldn't be out there trying to fly!

Another consideration of using an avband radio is that it's frequency band is international: you're not limited to country-specific frequencies like the ham bands, GMRS and FMS (if they exist) are.

As for radio choices, you can tell I was waffling about that. Most PPG and PPC enthusiasts fly in uncontrolled airspace and nowhere near an airport, "tower-challenged" or not, so it's hard to persuade them to buy an avband radio if they're not going to really use it. There's also the problem of which frequencies they'd use out in the middle of nowhere: Multicomm? Flight School? I used to be a general aviation flight instructor (CFII ASEL to you pilot types) and taught my students that while flying in uncontrolled airspace--and out of range of an airport traffic area--to keep their their radios tuned to 121.5 (distress frequency) and the nearest ARTCC/controlled facility. That way, if they need help or a downed pilot needs help, they would be at the ready to talk to someone.

The second problem with avband radios is education: PPG and PPC pilots would have to learn proper radio procedure and the arcane lexicon spoken between pilots and controllers. It isn't difficult to learn, but still some of those pilots may not want to bother learning it.

An added benefit of using an avband radio is that it's frequency band is international: you're not limited to country-specific frequencies like the ham bands, GMRS and FMS (if they exist) are.

With hamband radios, they have the advantage of accessing repeaters and a larger user base. If I were a downed pilot in the middle of nowhere and had only an avband radio, that would severely limit my odds of getting help since, as mentioned earlier, if no one's listening or is in range of you, you're hosed. Of course, there's the argument that if you're so "out there" that you're not within range of a repeater or somebody listening on simplex, then you're still hosed. :S

GMRS radios are a good option except that we run into the same problem: if you're downed and need help, will you be able to raise someone for assistance?

I guess it's a two-part problem: comm for your buds, G/A pilots, or an instructor, and comm for when you're downed and need help (hence the "power and distance" thinking). Me thinks I'll have to either rewrite a portion of the article or add something to it that makes known these concerns so the reader can decide which radio would be best for him or her, rather than have me try to persuade them to use one or the other. Personally, I'd use both avband and hamband radios since my flying involves flying in/near controlled airspace. Also, imagine the QSL card you'd get with "PPG aeronautical mobile" from Northern Idaho? That'd be worth some wall space and a few grid squares. :D

Now the tricky part: designing an antenna for PPG'ers so that there's no way for it to get sucked into the prop and not have any possibility of catching or tangling with any of the lines leading up to the wing.

W0IS
09-07-2008, 05:49 PM
The second problem with avband radios is education: PPG and PPC pilots would have to learn proper radio procedure and the arcane lexicon spoken between pilots and controllers. It isn't difficult to learn, but still some of those pilots may not want to bother learning it.

Well, I think the same thing probably applies to amateur radio. There are still procedures that need to be learned. When I got my pilot's license a long time ago, I don't remember too much time being spent on how to use the radio. Since they're not normally going to be talking to towers, etc., they really don't need to learn that terminology.


If I were a downed pilot in the middle of nowhere and had only an avband radio, that would severely limit my odds of getting help since, as mentioned earlier, if no one's listening or is in range of you, you're hosed.

Presumably, if it's an emergency, then somebody's probably going to be looking for them. (I assume they don't file formal flight plans, but still, it seems to me that it would be prudent to tell some responsible person where you're going and about when you're going to get back.) If so, eventually someone will be looking for them, and monitoring 121.5.

If it's a non-emergency, it seems to me that they would stay on the frequency they were last using to communicate with someone else.

I'm all for recruiting new hams, but for this application, it seems like an aviation radio is a much better choice. And those handhelds aren't a whole lot more expensive than ham gear, last I checked.

Of course, it would be a good idea to give the users a stern warning not to use the radios for non-aviation purposes.

K8ERV
09-07-2008, 06:05 PM
Now the tricky part: designing an antenna for PPG'ers so that there's no way for it to get sucked into the prop and not have any possibility of catching or tangling with any of the lines leading up to the wing.

Props are ok, they cool the pilot, but wings are for wimps.

TOM K8ERV Montrose Colo

NA0AA
09-07-2008, 06:56 PM
Use the spectrum assigned to aviation and use aviation band radios - in the old days, that was an expensive problem but today the aviation HT's are no more expensive than any of the good alternates.

Plus the license for a pilot to use aviation band is free for the asking and does not require study or a test.

Your pilots will have to learn to use either kind of radio, better they use aviation, in case they ever transition to a 'real' airplane where communications are manadatory. Also, aviation radio is MUCH less complex than FM based amateur communications.

There is not so much traffic that multiple frequencies are required, and if so, there are 720 channels on those AC radios.

As both a pilot and an Amateur, I say keep your pilots who are not interested in Amateur radio away from it - it's going to benefit neither user.

For emergency use, a cell phone is probably more effective than a Ham radio, particularly when any user of the radio must be licensed. OTOH, a ground aircraft radio can be operated by any handy user.

As to antennas - use the rubber duck on the HT if you wear the radio - that way there is nothing to connect, disconnect or cords to break.

KD6WAG
09-07-2008, 08:25 PM
Your pilots will have to learn to use either kind of radio, better they use aviation, in case they ever transition to a 'real' airplane where communications are manadatory. Also, aviation radio is MUCH less complex than FM based amateur communications.
I agree 100%.


As both a pilot and an Amateur, I say keep your pilots who are not interested in Amateur radio away from it - it's going to benefit neither user.
Again, I couldn't agree more! 110% on this issue!!!


As to antennas - use the rubber duck on the HT if you wear the radio - that way there is nothing to connect, disconnect or cords to break.
EXCELLENT!

I might add that if in the event you're in a "downed aircraft" situation, virtually every single airliner flying overhead AND S&R aircraft are monitoring 121.5 as others here have already noted.

In fact, out in remote area of the deserts where there are NO ham repeaters, it's actually better to have a radio with 121.5 capabilities. I read in "Outdoor Life" magazine of some Alaskan hunting guides that purposely carry hand held aviation radios along with the new satellight location beacons (400 mHz) in the event they have a life & death urgency that they need to communicate with an overpassing airliner. Airliners can be seen from everywhere virtually in the country. Your ultra light pilots can use 121.5 to save their life in the event they are downed too. Airliners, military and civilian aircraft usually always monitor 121.5, as well as EVERY SINGLE Air Traffic Control facility (Towers, TRACONS, Centers, FSS's etc...) in the U.S. Passing aircraft that can be seen on the ground from a downed ultra light pilot can get on that frequency and call for emergency help.

I really think you should scrap the whole idea of using ham radio for air-to-air communication on a "REGULAR" or as your "PRIMARY" operating communicator. Stick with an Aviation radio. Ham's are used for hobbies for the most part. Not critical "REGULAR" use of daily air-to-air communications.

Yes, during emergencies (floods, fires, earthquakes, civil unrest etc...) ham's activate. But, there is really no 2M or 70cm DESIGNATED frequency for emergencies that is monitored 24/7. On the other hand, 121.5 is ALWAY monitored, 24/7 by someone or another.

I might point out too that while I've traveled in vast areas of the western U.S. including deserts, many times I can "ker-chunk" a 2M repeater and nobody ever answers. The lights are on, but nobody's home....more or less.

Good luck and let us know what you end up doing. Perhaps you can continue to write your very informative article, but just tweak it a bit. Perhaps go into serious comparrison & contrasting amoungst all of the different forms of radio communication and try to settle on the fact that for you "flyers," really need a radio that is the MOST practical for your hobby. That radio being a "flyer's" radio. An aviation radio.

K7RQ
09-08-2008, 01:50 AM
My last 24 years on the job was in the avionics business. I have no ultralight flying experience but from observing them buzzing around near where I live, I would expect that ambient noise would be a major problem in those wide-open aircraft.
FRS radios are not the answer, in my opinion.
I've been out of the business since 1991 but I remember that King/Bendix and Icom, and I'm sure others have aviation band handhelds on the market. You need something that can be connected to a remote push to talk circuit and a helmet with a good noise-cancelling boom mike and headphones inside. I'd recommend checking with a reliable avionics shop to see what's available.
The antenna can be as simple as a 23 inch piano-wire whip mounted on some metallic structure, if you go that route.

Hal, K7RQ

WF7A
09-08-2008, 04:38 AM
What gets my goat is that ultralight flyers will spend ten grand for an aircraft but won't spend $200 for a radio to go with it. :S

It sounds like the avband radio route sounds best for these guys, so that's where I'll go with the article. Thanks again, guys!




I've been out of the business since 1991 but I remember that King/Bendix and Icom, and I'm sure others have aviation band handhelds on the market. You need something that can be connected to a remote push to talk circuit and a helmet with a good noise-cancelling boom mike and headphones inside. I'd recommend checking with a reliable avionics shop to see what's available.
The antenna can be as simple as a 23 inch piano-wire whip mounted on some metallic structure, if you go that route.

Hal, K7RQ

Indeed, Hal, Vertex and Icom make great avband handhelds, complete with VOR radial tracking...which will become an obsolete feature in a couple of years when the FAA decomissions all the VORs and NDBs to save $$$.

Regarding PTT switches: A couple of helmet manufacturers have a transmitter PTT button mounted directly on a headset's earcup...which I think is a dumb place to have it since you have to take your hand off a steering or other control every time you want to transmit.

Speaking of which, I'm curious why throat mikes aren't popular--you wouldn't have to worry about trying to outshout an engine and prop if you used one...though if you have acid reflux that could cause some interesting sounds to be inadvetently transmitted. :)

The piano wire whip antenna sounds like a good idea, but it being mounted on metal or on a person wouldn't it cause coupling issues?

K7RQ
09-08-2008, 04:45 PM
Yes, I remember those handhelds with a VOR radial readout. The problem was that com transmissions were primarily vertically polarized while VOR's are horizontal. You had to hold the handheld flat to get a decent VOR signal on the attached antenna. I don't think the whip would be much of a problem. It doesn't take much metallic structure to provide a ground plane of sorts on that frequency.
And I have some experience with throat mikes. We had them in the army, in vehicles. They are lousy! None of the highs in the speech spectrum come through. I remember someone describing them as making the operator sound like he was in a fur-lined pickle barrel! But we had another one called a lip mike. That was a little square plastic thing that sat on your upper lip and had straps with loops that went around your ears. It looked like Adolf Hitler's moustache. I think it was a "contact" mike that had no holes in it for the sound but rather worked on vibration. Those worked very well in our noisy half-tracks and the audio was crisp and clear. But I haven't seen one of those in years. If you could find any of them, they would work with modern avionics gear, being carbon mikes.
Hal

NA0AA
09-08-2008, 04:55 PM
What gets my goat is that ultralight flyers will spend ten grand for an aircraft but won't spend $200 for a radio to go with it. :S


Indeed, Hal, Vertex and Icom make great avband handhelds, complete with VOR radial tracking...which will become an obsolete feature in a couple of years when the FAA decomissions all the VORs and NDBs to save $$$.


Well, regarding the $$, yea, if they want to get by with $20 radios, that's fine, but if they want a real, working tool, then spend the $200 and get a nice ICOM avband HT and go with it. Any good quality Amateur radio is going to cost at least $100 before you add any accessories.

Question: Can you cite information regarding the VOR shutdown schedule? I just met with some coasties who work LORAN and they informed me that there are no plans to shutdown LORAN since the Gov't has determined that making the GPS system inaccurate was not as difficult as they thought, so they are keeping the ground based system as well.

WRT antennas:

You can use a whip mounted on anything - I have a 1/4 wave of bronze brazing wire soldered into a PL-259 that works fine, you can do that or use stainless wire in a Larson type mount as well.

VK2AKG
09-08-2008, 05:45 PM
Speaking of which, I'm curious why throat mikes aren't popular in addition to the fidelity issues already discussed, wearing one for 8 hours should remove that curiosity. 73 Frank vk2akg

WF7A
09-09-2008, 04:02 AM
Question: Can you cite information regarding the VOR shutdown schedule? I just met with some coasties who work LORAN and they informed me that there are no plans to shutdown LORAN since the Gov't has determined that making the GPS system inaccurate was not as difficult as they thought, so they are keeping the ground based system as well.

I don't know about LORAN being on the butcher's block but here's what AOPA had to say:

FAA intends to reduce VOR network soon

By AOPA ePublishing staff
The FAA has confirmed to AOPA that it is making plans to reduce the network of VORs across the country, beginning in 2010.
However, AOPA members are not quite convinced that a widespread VOR reduction is acceptable. Survey information shows that only about half of AOPA members believe a significant number of VORs can be eliminated without affecting their flight operations.
“Clearly this marks a big step forward in pilot acceptance of GPS and reduced reliance on VORs, but members are still saying ‘not yet,’” said Andy Cebula, AOPA executive vice president of government affairs.
Despite high levels of GPS use, FAA regulations require pilots who use GPS to also carry a primary navigation system, and for general aviation the primary system available for regulatory compliance is VOR. Second-generation GPS systems that incorporate the Wide Area Augmentation System (WAAS) do not require VOR as a backup, but the current state of equipage in the GA fleet is about 15 percent.
In a letter (http://download.aopa.org/epilot/2008/080828vor.pdf) to the FAA, AOPA cautioned the FAA against making plans to reduce VORs because there are several key issues currently preventing the dismantling of the VOR infrastructure. Barriers include pilot confidence in relying solely on GPS signals and the lack of systematic implementation of area navigation. AOPA pointed out that the FAA should broaden its focus to ensure that all IFR flights can be conducted from takeoff to touchdown with an IFR GPS, regardless of the airports involved. Ultimately, the FAA needs to change its policies to reduce GA’s reliance on VORs."

There's another problem: Most FMS-equipped planes depend on DME auto-tuning in addition to GPS signals, so it'd be kind of silly to decommission VORs while there are lots of FMS-equipped planes flying around. :S

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