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For the radio stations in Wilma's path...

J

JasonW

Guest
Hello All,

I know the staffs of radio stations in Florida and surrounding areas are busily preparing for the possible arrival of Hurricane Wilma. I wanted to suggest something that would allow these stations to remain on the air even if their towers and/or generators are destroyed by the storm.

A Part 15 AM transmitter can be run off a car's battery or alternator (using a cigarette lighter adapter), and if a full-size 1/4 wavelength or 1/2 wavelength wire antenna is used (held up by mylar balloons or a tall building), even its 0.1 watt signal can cover several square miles. A 1/2 wavelength wire antenna would require only a ground rod to function effectively and would have a low angle of radiation, and it would need only a simple L-Match ATU that could be made in minutes from an AM pocket radio ferrite loopstick and a small variable capacitor. Part 15 AM transmitters such as the InfoMAX http://www.theradiosource.com/products-infomax.htm , Talking House www.talkinghouse.com and www.actradio.com , and TalkingSign www.talkingsign.com are ideal for this application. They have microphones and built-in auto-repeat 5 minute non-volatile flash audio memories that can broadcast repeating public service messages. While the FCC Part 15 AM rules prohibit total antenna + antenna feed (if any) + ground lead lengths greater than 3 meters, I'm certain that rule would be waived in a disaster situation, especially if all full-power licensed stations in a community were knocked off the air.

I hope this information will be helpful. -- J. Jason Wentworth
 
>
> I wanted to suggest something
> that would allow these stations to remain on the air even if
> their towers and/or generators are destroyed by the storm.

Thats great... now what programming should these stations run considering there's a good chance, if the transmitters generators fail, the studios might too? I can broadcast dead air from my vehicle all day long - but if I don't have content, what good will it do anyone?<P ID="signature">______________
vide0 killed the radi0 star</P>
 
I think the engineers would know HOW to put a station back on the air as quckly as possible...a LPAM xmtr (50-250watt) is easily gotten ahold of and a wire antenna (Inverted 1/4wave L or even a 1/2wave inverted V) is easy to put up and match to....not the best in the world but better than your idea and a REAL broadcast signal...I worked at one broadcast station that ran off a 1/4w Inv L for YEARS after they lost their main tower..it worked ok...

Dont fret Jason....they dont need Part 15 stuff when REAL radio stuff is available that works (LPAM stations can run on 12V batteries too...but then if they have a generator, why?) 500w and higher solid state xmtrs are easily found and are not that big......so much for playing with Part 15 stuff..

> Hello All,
>
> I know the staffs of radio stations in Florida and
> surrounding areas are busily preparing for the possible
> arrival of Hurricane Wilma. I wanted to suggest something
> that would allow these stations to remain on the air even if
> their towers and/or generators are destroyed by the storm.
>
> A Part 15 AM transmitter can be run off a car's battery or
> alternator (using a cigarette lighter adapter), and if a
> full-size 1/4 wavelength or 1/2 wavelength wire antenna is
> used (held up by mylar balloons or a tall building), even
> its 0.1 watt signal can cover several square miles. A 1/2
> wavelength wire antenna would require only a ground rod to
> function effectively and would have a low angle of
> radiation, and it would need only a simple L-Match ATU that
> could be made in minutes from an AM pocket radio ferrite
> loopstick and a small variable capacitor. Part 15 AM
> transmitters such as the InfoMAX
> http://www.theradiosource.com/products-infomax.htm , Talking
> House www.talkinghouse.com and www.actradio.com , and
> TalkingSign www.talkingsign.com are ideal for this
> application. They have microphones and built-in auto-repeat
> 5 minute non-volatile flash audio memories that can
> broadcast repeating public service messages. While the FCC
> Part 15 AM rules prohibit total antenna + antenna feed (if
> any) + ground lead lengths greater than 3 meters, I'm
> certain that rule would be waived in a disaster situation,
> especially if all full-power licensed stations in a
> community were knocked off the air.
>
> I hope this information will be helpful. -- J. Jason
> Wentworth
>
 
> Dont fret Jason....they dont need Part 15 stuff when REAL
> radio stuff is available that works.


I read up on all this guy's posts... is he like a sales rep for part 15 transmitters or something?<P ID="signature">______________
vide0 killed the radi0 star</P>
 
0.1 watts *can* beat 50,000...

I guess no good deed goes unpunished...

No, I don't sell transmitters (Part 15 or any other kinds), but I *have* been in natural disasters (an earthquake and two hurricanes) where all radio stations were knocked off the air.

If your tower and/or generator are destroyed in a disaster, a Part 15 AM transmitter and a balloon-supported 1/2 wavelength wire antenna sure beat the hell out of the alternative, which is radio silence.

Studio? You don't need one in an emergency. Content? Just hearing a local official known to the people (the mayor, sherriff, fire chief, etc.) can go a long way to calm tensions and boost morale. A Florida gentleman I'm corresponding with runs a Part 15 AM station is his community, and he was the *ONLY* radio station on the air for many days after the 2004 hurricanes. He re-broadcast NOAA weather radio disaster recovery information and live interviews with local officials, and his lone broadcast outlet was and is much appreciated in his community. Sometimes 0.1 watts *can* beat 50,000... -- Jason
 
Re: I want some of what you're smoking!

> Hey, a portable generator, an exciter, and an antenna beat a
> part 15 ANY day.
>

No kidding. Especially if your co- and adjacents are off air. Part 15, as much fun as it is, will only cover a neighborhood at best. Shoot, my Kima barely gets upstairs.
 
Re: I want some of what you're smoking!

> No kidding. Especially if your co- and adjacents are off
> air. Part 15, as much fun as it is, will only cover a
> neighborhood at best. Shoot, my Kima barely gets upstairs.
>


But see, you're not DOING it right... you're supposed to hook the antenna for that to a balloon....and fly it high in the air... in the middle of a hurricane... that already took down your umpteen hundred foot tall tower. THATS why your radio doesnt work :) You've got it all wrong!<P ID="signature">______________
vide0 killed the radi0 star</P>
 
Re: I want some of what you're smoking!

> Hey, a portable generator, an exciter, and an antenna beat a
> part 15 ANY day.

Of course, but only if they aren't damaged beyond repair or destroyed--thank you for belaboring the obvious.

I am speaking of situations in which you may not have these available due to the severity of the disaster. A Part 15 AM transmitter can run for hours off a car battery, and it can also be powered by a small solar panel. -- Jason
 
Re: I want some of what you're smoking!

> > Hey, a portable generator, an exciter, and an antenna beat
> a
> > part 15 ANY day.

> No kidding. Especially if your co- and adjacents are off
> air. Part 15, as much fun as it is, will only cover a
> neighborhood at best. Shoot, my Kima barely gets upstairs.

The Kima is a Part 15 FM transmitter. I'm referring to Part 15 *AM* transmitters, which are totally different in terms of the permitted power level, which is 0.1 watts--many times the allowed Part 15 FM power output. Fed to a 1/2 wavelength wire antenna worked against a good ground, a 0.1 watt AM signal can be heard for miles. Ham radio operators using similar very low power levels achieve such local coverage all the time on their 160 meter band, which is just above the AM broadcast band (1800 kHz - 2000 kHz). -- Jason
 
Re: I want some of what you're smoking!

> The Kima is a Part 15 FM transmitter. I'm referring to Part
> 15 *AM* transmitters, which are totally different in terms
> of the permitted power level, which is 0.1 watts--many times
> the allowed Part 15 FM power output. Fed to a 1/2
> wavelength wire antenna worked against a good ground, a 0.1
> watt AM signal can be heard for miles. Ham radio operators
> using similar very low power levels achieve such local
> coverage all the time on their 160 meter band, which is just
> above the AM broadcast band (1800 kHz - 2000 kHz). --
> Jason
>


I AM a ham operator. I KNOW what we can do and can't do. But if I own or manage an FM station, and my tower goes down. I'd much rather work on getting something up on the frequency my listeners are USED to hearing me on. Not changing frequencies and bands totally. I don't know about you, but I don't go combing the AM band for low power AM stations to listen to. My listeners wouldn't know to switch bands and listen for me there anyway.

-.. . -.- -- ..... .-.<P ID="signature">______________
vide0 killed the radi0 star</P>
 
Re: I want some of what you're smoking!

Engineers are always good at having a fall back plan, its when corprate dosent see the need for such a plan (they see $$$$$ being spent).
But once the stations off for several days they fire the engineer for not having the station back up within 2 hours. GO FIGURE.......
 
Re: I want some of what you're smoking!

> > > Hey, a portable generator, an exciter, and an antenna
> beat
> > a
> > > part 15 ANY day.
>
> > No kidding. Especially if your co- and adjacents are off
> > air. Part 15, as much fun as it is, will only cover a
> > neighborhood at best. Shoot, my Kima barely gets upstairs.
>
>
> The Kima is a Part 15 FM transmitter. I'm referring to Part
> 15 *AM* transmitters, which are totally different in terms
> of the permitted power level, which is 0.1 watts--many times
> the allowed Part 15 FM power output. Fed to a 1/2
> wavelength wire antenna worked against a good ground, a 0.1
> watt AM signal can be heard for miles. Ham radio operators
> using similar very low power levels achieve such local
> coverage all the time on their 160 meter band, which is just
> above the AM broadcast band (1800 kHz - 2000 kHz). --
> Jason

Hmmm must be deeply inhaling.....I have worked 160mtrs over the years...100mw?? (YOU ever work 160mtrs BTW?) Forget it...the background natural noise/static kills that on any given day or night...I know NOONE that runs that low QRP on 160....maybe 5-10watts...but then they have a killer antenna....(not a simple 1.4wave).....Running 50watts to a vertical antenna can cover some miles IF the BC band is quiet....but given any freq is used outside Florida, 100mw up to 50-100watts would be killed by skywave at night....daytime, the signal would cover some distance...but given the number of stations in Florida, and the preparation since the last hurricane, I think AM stations will be ready.

Again, LPAM xmtrs work off 12V DC and do more than 100mw....I could put a 100watt solid state xmtr on out of a car if needed....
FORGET Part 15....thats playtoys...
 
Re: I want some of what you're smoking!

The Pixie II is a 150 milliwatt, 160 meter (or 80 meter, depending on the crystal used) QRP ham transceiver. Users easily achieve ranges of 100 miles and more via NVIS (Near-Vertical Incidence Skywave) propagation.

Part 15 AM stations with well-matched 3 meter tall antennas routinely reach listeners 1/2 mile to 2 miles away with clear signals, so using an efficient full-size antenna for emergency broadcasting would provide much greater range.

If you have a bigger back-up transmitter available (the 30 watt and 60 watt LPB units are quite good), more power to you (pun very much intended). I was simply trying to point out that even Part 15 power levels can cover significant listener areas if used with an efficient antenna. -- Jason

> > > > Hey, a portable generator, an exciter, and an antenna
> > beat
> > > a
> > > > part 15 ANY day.
> >
> > > No kidding. Especially if your co- and adjacents are off
>
> > > air. Part 15, as much fun as it is, will only cover a
> > > neighborhood at best. Shoot, my Kima barely gets
> upstairs.
> >
> >
> > The Kima is a Part 15 FM transmitter. I'm referring to
> Part
> > 15 *AM* transmitters, which are totally different in terms
>
> > of the permitted power level, which is 0.1 watts--many
> times
> > the allowed Part 15 FM power output. Fed to a 1/2
> > wavelength wire antenna worked against a good ground, a
> 0.1
> > watt AM signal can be heard for miles. Ham radio
> operators
> > using similar very low power levels achieve such local
> > coverage all the time on their 160 meter band, which is
> just
> > above the AM broadcast band (1800 kHz - 2000 kHz). --
> > Jason
>
> Hmmm must be deeply inhaling.....I have worked 160mtrs over
> the years...100mw?? (YOU ever work 160mtrs BTW?) Forget
> it...the background natural noise/static kills that on any
> given day or night...I know NOONE that runs that low QRP on
> 160....maybe 5-10watts...but then they have a killer
> antenna....(not a simple 1.4wave).....Running 50watts to a
> vertical antenna can cover some miles IF the BC band is
> quiet....but given any freq is used outside Florida, 100mw
> up to 50-100watts would be killed by skywave at
> night....daytime, the signal would cover some distance...but
> given the number of stations in Florida, and the preparation
> since the last hurricane, I think AM stations will be ready.
>
>
> Again, LPAM xmtrs work off 12V DC and do more than
> 100mw....I could put a 100watt solid state xmtr on out of a
> car if needed....
> FORGET Part 15....thats playtoys...
>
 
Re: I want some of what you're smoking!

> I AM a ham operator. I KNOW what we can do and can't do.
> But if I own or manage an FM station, and my tower goes
> down. I'd much rather work on getting something up on the
> frequency my listeners are USED to hearing me on. Not
> changing frequencies and bands totally. I don't know about
> you, but I don't go combing the AM band for low power AM
> stations to listen to. My listeners wouldn't know to switch
> bands and listen for me there anyway.

I prefer AM, period. FM audio has a "dry," "sterile" sound (due to the limiting) that I find uncomfortable to listen to for long durations. If you can arrange for a crane to hold up a temporary two-bay FM antenna if you lose your tower, great. But if you can't, your listeners needn't have to search to find you on the AM band. You would only need to air occasional PSAs saying, "In the event of a natural disaster that takes us off the air, you can find us at XXX kHz on the AM dial" or something similar. An LPB-30 or -60 (*or* a Part 15 AM unit, if that's all you have at the time) and a full-size wire antenna will get you back on the air with a decent coverage area. -- Jason
 
Re: I want some of what you're smoking!

> Engineers are always good at having a fall back plan, its
> when corprate dosent see the need for such a plan (they see
> $$$$$ being spent).
> But once the stations off for several days they fire the
> engineer for not having the station back up within 2 hours.
> GO FIGURE.......

Exactly! That's the only reason I brought up the very inexpensive Part 15 AM emergency broadcasting option at all. Here in Fairbanks, Alaska, we have lost ALL of our several AM, FM, and TV stations simply from power outages (no one's back-up generators kicked in).

One afternoon last year our area lost power, and when I scanned the bands for some news on the situation, I heard *NO* commercial stations. Only our local NOAA Weather Radio station remained on the air. The power was restored within an hour, but I was left wondering if they could do any better if there had been an earthquake (an hour is an eternity when it's an emergency situation).

That's the only reason I suggested a Part 15 AM transmitter as a cheap, last-ditch, "in your back pocket" back-up option. In an emergency you could simply take it out of the trunk of a car, plug it into the cigarette lighter for power, toss a full-size thin wire antenna up into a tree (or raise it with a common helium party balloon), ground the transmitter to the car chassis (and/or lay out a 1/4 wavelength counterpoise wire on the ground) and use its built-in microphone (or a separate mike--they have jacks for them) to broadcast what's going on. If you used a balloon-supported wire antenna, you could possibly drive (depending on road conditions) to the local emergency operations center so that officials could speak directly to the public. Or, you could stay at the radio station and relay information from them through the Part 15 AM transmitter using their VHF or UHF radio systems.

Would it be better if a radio station had a more powerful emergency back-up transmitter with a portable power source? Absolutely! But if an "el cheapo" radio station decides not to spend money for such "niceties," the station's engineer (or any staff member, for that matter) could save the day with a ~$200 Part 15 AM transmitter and a few dollars' worth of wire for an antenna. -- Jason
 
Re: 0.1 watts *can* beat 50,000...

> I guess no good deed goes unpunished...
>
> No, I don't sell transmitters (Part 15 or any other kinds),
> but I *have* been in natural disasters (an earthquake and
> two hurricanes) where all radio stations were knocked off
> the air.
>
> If your tower and/or generator are destroyed in a disaster,
> a Part 15 AM transmitter and a balloon-supported 1/2
> wavelength wire antenna sure beat the hell out of the
> alternative, which is radio silence.
>
> Studio? You don't need one in an emergency. Content? Just
> hearing a local official known to the people (the mayor,
> sherriff, fire chief, etc.) can go a long way to calm
> tensions and boost morale. A Florida gentleman I'm
> corresponding with runs a Part 15 AM station is his
> community, and he was the *ONLY* radio station on the air
> for many days after the 2004 hurricanes. He re-broadcast
> NOAA weather radio disaster recovery information and live
> interviews with local officials, and his lone broadcast
> outlet was and is much appreciated in his community.
> Sometimes 0.1 watts *can* beat 50,000... -- Jason
>

Of course, the moment you connect a 1/2 wave antenna and the balloon, it is no longer a legal Part 15 device!

:)<P ID="signature">______________
</P>
 
> >
> > I wanted to suggest something
> > that would allow these stations to remain on the air even
> if
> > their towers and/or generators are destroyed by the storm.
>
>
> Thats great... now what programming should these stations
> run considering there's a good chance, if the transmitters
> generators fail, the studios might too? I can broadcast
> dead air from my vehicle all day long - but if I don't have
> content, what good will it do anyone?
>

Hmmm.. Here's a thought. If a person could get a weather observation balloon and supply voltage/power via the teather (using car voltage if nothing else), could a guy build up effectively a translator that would have a tuner on one end of the FM band that would be connected to a transmitter on the other end of the band, thereby translating whatever it hears on the input frequency? After a storm cleared and everyone was scrambing around trying to get their junk on the air, a setup like that put on a normally used frequency in the area might prove useful to dissimating information to the public. The input frequency transmitter could be sent to the local athorities to plug into their car cig. lighter with a mag-mount and transmit a very small signal that would "STL" it up to the balloon. from several hundred feet up, in most cases, a guy should able to hear even a weak part 15 on a decent outside antenna for severl miles. I actually think a transmitter of a watt or so up on a balloon at several hundred feet would get out pretty good. I would be supprised if it didn't get at least 5 miles on a car stereo.

I understand what most of the people are saying here about this guy, however, I feel he's not that far off base really. Height can do some amazing things, epecially on the FM band. (he was saying AM, but honestly I think FM would work better for this app) I personally have had some experience with putting FM stuff at about 100mw on building-tops and having several mile coverage. Without many other signals to get blanketed by and more transmitting height, it's bound to work even better than what I've played with on FM.

That's my 2 cents worth.. :)

<P ID="signature">______________
--- THE Insultant ---</P>
 
Re: 0.1 watts *can* beat 50,000...

>
> Of course, the moment you connect a 1/2 wave antenna and the
> balloon, it is no longer a legal Part 15 device!
>

THANK YOU.

I've been waiting for someone to come out and say it!!!
 
Re: 0.1 watts *can* beat 50,000...

> Of course, the moment you connect a 1/2 wave antenna and the
> balloon, it is no longer a legal Part 15 device!

If you happened to hear a CB radio distress call that came from beyond the legally-allowed range for CB transmissions (it *does* happen sometimes under unusual skip conditions, even with legal power levels), would you ignore the person because it's illegal to reply over such a range? -- Jason
 
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