Assuming there is a way of getting a long wave radio in the car, let me ask....
Given 1-Watt and a decent ground radial vertical antenna, how far do you think over-the-road reception would be?
It is always disappointing that I can only follow KDX for 2-blocks when driving to nearby destinations.
I had the same question regarding shortwave at 13.560kHz, but Bruce Dog Radio Studio 2 says his brother had shortwave in the car and it was spoiled by noise produced by the car itself. Probably clicks, statics and whatnot.
Well considering what we can do with the regular Part 15,
I wouldn't be surprised if we got 2 miles out of the Longwave Transmitters.
I posted the results of a simulation of the final stage of a 170 kHz tx. here: http://www.part15.us/node/3008
I did it this way since I am not clever enough to post attachments except to a new post.
Neil
Neil, I just went over to node/3008 and indeed it looks very promising.
I think we probably have as much fun contemplating and daydreaming our micro-radio-empires as we have operating them when they exist.
Some people rattle on about "the pursuit of happiness," but Part 15 radio IS happiness.
It gets so bad sometimes it becomes slap happiness.
If only it impressed the women.
P.S. The way you devised the attachment is clever in itself. It does the job.
First of all, Neil's simulation is great.
And I love the network logos.
Most of the longwave Part 15 experimenters
use morse code or various digital modes.
I don't think too many people have tried AM
between 160 to 190,
so we should definitely give it a go. I believe
this to be quite a bit harder than Part 15 on
the AM broadcast band, but who knows what
we may come up with. The 13 MHz project
has shown that we can work together making
things that nobody has ever done before. And
the new carrier current info on the board is
probably going to eventually get a bunch of
us doing that, so the more the merrier!
There is an absolutely wonderful radio source
called "The Low and Medium Frequency Experimenters
Scrapbook. It was written by the late Ken Cornell, W2IMB.
He had 10 editions, starting in 1972, until about 1996,
when he passed away. This book is very fondly remembered
by many people, but almost impossible to find. If any of
you guys out there have it in the attic, or something, it is
a real treasure. I used to have the first edition, and it is
gone forever.
I just got off the phone with an old buddy who had a longwave
morse code beacon (cw) on 184.0 kHz about 20 years ago. It
was heard in five states, but remember the states are very
small up here. I think the furthest reception report came from
New Hampshire, and he was in West Hartford, CT. Power was
1 watt DC input into the transmitter which fed a 50 foot vertical.
He also had a medium wave morse code beacon here on 1625 kHz
Power was 100 mW. The antenna was 3 meters. This beacon was
also heard in New Hampshire.
My friend had one great great advantage. He set the beacons up
at an old AM broadcast band transmitter site. The tower was
down, but the ground system was still there. So he had the
use of a real broadcast station ground system.
There was no power at the site so he put up some solar cells
and charged a battery that ran the beacons. When I think about
it now, it was a really cool project.
Best Wishes,
Bruce, Dog Radio Studio 2
Bruce, you have brought up something I am wondering about.... namely, how AM will sound on long wave. Actually, you have DXed longwave broadcasting stations, so that should be an idea of the sound, if your reception was good enough to tell.
What is the bandwidth of the LW frequencies... are they the same as medium wave?
And I got to wondering about the history of long wave in the U.S. Did we ever have long wave radio stations before regular medium wave got going?
AM on LW should sound just like normal AM radio. If I'm not mistaken the bandwidth is exactly the same, except Longwave is in 9 khz steps.
Maybe all the details for building a LW transmitter can be linked and attached here on the thread, but if it would help, I would be available to provide a dedicated web page particularly for transmitter and antenna plans, as I did with the Big Talker shortwave project.
Think about it and cast your votes here and the voting deadline is October 10th.
To see why the United States never had a Long Wave
broadcast band, we'd have to really dig back into
the history back then. I'm not sure what happened,
I'll have to dig into the books.
There is one little known story that comes from 1921.
The Jack Dempsey-Georges Carpentier heavy weight
championship fight was going to be held in Jersey City,
New Jersey. People were calling it "The Fight Of The Century."
Ham radio operators put together the first ever sports radio
network, and it was on Long Wave!
This seems unbelievable, but 300,000 people heard the broadcast
up to 400 miles from the championship fight! The were all in
auditoriums and arenas. Hundreds of hams built Long Wave receivers
for 187 kHz. They also built PA systems. One arena was so big it
held 8000 people, and the PA system covered the whole arena without
any trouble. So here were all these people listening to this championship
heavy weight match, and most of them had never even heard radiotelephony
before!
The transmitter was a 3 kW job built by General Electric that transmitted the
announcers audio on 187 kHz. The transmitting antenna was 680 feet long.
It consisted of 6 wires on 30 foot spreaders. One end of the wire array was
attached to the top of a 400 foot tower. the other end was hooked to
a clock tower at a railroad terminal. The antenna current was about 25 amps!
The 187 kHz frequency was a Navy frequency. Special permission to use it for
the broadcast was requested and granted.
J.O. Smith, ham radio callsign 2ZL, handled the installation of the transmitting
equipment and the audio feed. That 3 kW GE transmitter was considered to
be state of the art at the time.
I think I have a few other Long Wave stories to tell, I just have to think about
them for a little while.
Maybe there was no Long Wave broadcast band because the U.S.
military had the spectrum first.
Best Wishes,
bruce, Dog Radio Studio 2
Here's a few other odds and ends.
23 and 33 kHz mystery.
I used to hear some kind of digital protocol
on Long Wave. This was really low. The frequencies
were 23 kHz and 33 kHz. They both sounded the
same. They sounded sort of like radio teletype.
That was years ago. I didn't ever figure out what they
were or were they were from. Both signals are gone now.
WGU-20 179 kHz.
WGU-20 was nicknamed, "The Last Radio Station." Built in
the 1970s and operated until the late '70s from near
Washington, DC, it was supposed to be part of a Long Wave
alert network for an impending enemy atomic bomb attack.
There was supposed to be a network of these alert stations
that covered the whole U.S. Special emergency receivers were
supposed to be part of home entertainment equipment, such
as TVs, radios, and even (I can hardly believe this) smoke alarms!
WGU-20 used the very first 50,000 watt solid state AM transmitter
ever made. I was fortunate to actually hear it. Lacking Long Wave
receiving equipment myself, I went to a friends house. When my friend
tuned his Drake SW-4A to 179 kHz, WGU-20 would be very strong,
day and night. Unfortunately, no manufacturers were interested in
putting Long Wave emergency receivers into TVs, radios, or whatever.
And almost nobody had LWBC receiving gear, so WGU-20 was turned
off in the late 1970s. When it was operating, it transmitted time signals
and a description of it's mission (which never came to pass.)
WGU-20 had a gigantic ground wave, and hearing it's Maryland transmission
in Connecticut was absolutely no problem, day or night.
TUK, 194kHz.
Another station that we always tuned in was TUK, in Nantucket, MA,
on 194 kHz. It was a navigational beacon for aircraft coming into
the upper east coast. It could be heard way out over the Atlantic,
so it was perfect for aircraft navigation.
We liked it because it was an AM station that transmitted navigation
data and voice information. It was just plain cool, and what a signal!
The Long Wave rumor mill says TUK is still on, but is now just transmitting
it's basic identifier in Morse Code. I'll have to check that. The TUK
designation is not a callsign, but sort of an identifier, that is (I guess)
easy to recognize in Morse Code, because it repeats itself over and over.
Some long wave beacons have identifiers that are similar to their locations,
such as PWA, in (get this) Pentawawa, Ontario. I have heard PWA many times
over the years. It is just below the AM BCB, I'll have to look it up and
see what freq. it is on.
Atlantic 252.
Altantic 252 was a very very famous rock and roll long wave station that
was - yup, you guessed it, on 252 kHz. It broadcast to the U.K. and ireland
between 1989 and 2002. By the end of it's run, most people in that area
of the world were listening to rock on FM radio, so Atlantic 252 was shut off.
In it's heyday, it was a big deal. I believe that somewhere out there, there
is a Part 15 station that calls itself Atlantic 252, in honor of that great station.
I was thinking of using that name for my Part 15 station at one time, for the
same reason.
I may have a few other little bits and pieces, so stand by if you want to.
Bruce, Dog Radio Studio 2
Absolutely love those long wave stories! And maybe I can bring a possible solution to that signal you once heard in the very very long wave, you said it was 23kHz......
I was just on the WWV website yesterday reading about the time radio station from Boulder, Colorado and Somewhere, Hawaii, and in their history they said they ended their time station at 20kHz and gave the year. Maybe that was what you heard.
That "Fight of the Century" story is every bit as epic as the often heard Orson Welles "War of the Worlds" story. Wow.
Another great general radio tale is how movie theaters tried to lure people back to watching movies by playing "The Amos and Andy Show" on the sound system prior to the feature film.
Talk about multi-media.
Wow, I didn't know that story about the movie
theaters playing "Amos and Andy," that's really
interesting.
Here's a few more little Long Wave things.
The beacon in Pentawawa, Ontario, is YWA,
and it can be heard by some AM radios that
tune fairly low. It's on 516 Khz. I've heard
it a bunch of times. There are two other
beacons that can be heard at the bottom of
the AM band. One is HEH, in Newark, OH,
on 524 kHz. The other one is OS, in Columbus, OH,
and that's on 515 kHz. Hmmmm. That's getting a
little bit down there. i don't know if my AM radios
could go that far down.
There is one other signal that is widely heard below the
AM BCB. It is the NAVTEX service, which basically sends
printed material to maritime vessels via radio. It's on
518 kHz. No problem hearing them here in Connecticut.
They are very strong here. The digital protocol they use
is SITOR-B, which I know nothing about. But it sounds
like a continuous bunch of rapidly changing beep noises.
Oh yeah, the 20 kHz station, WWVL, was turned off before
I ever listened to Long Wave. So the energy on 23 kHz must
have been from something else. Also, WWV had a 25 MHz
transmitter, which was turned off years ago. Well, at least
2.5, 5, 10, 15, and 20 MHz are still there.
Yup, the world below 535 kHz is a lot of fun!
Bruce, Dog Radio studio 2
Always interesting to think about the fact that our brainwaves are frequencies down in the ELF (Extra Low Frequency) spectrum, 3-24Hz. Then there is a "guard band" up to 20Hz, where audible hearing starts and goes up for a bunch of octaves to 20kHz. Then there is a bigger "guard band" above which the one-octave of visible colors and light is experienced, in the NanoWave region of the spectrum. Those natural "white spaces" is where we reside with our bitty Part 15 signals sparkling alive and glorious.
Oh dear, I flipped into some kind of poetry zone, cut the carrier, cut it now.
In the book 2001, A Space Odyssey,
(not the movie) Arthur C. Clarke
described extraterrestrial beings that
saw things and communicated via
X-rays, ultraviolet, and such.
Doesn't sound so far off to me.
Bruce, Dog Radio Studio 2
The year was 1961 and I had been looking for something fun to play with involving electronic communication. I was in high school and I had seen projects at science fairs where folks hooked a lamp to an amplifier and sent music over a light beam to a photocell driven amplifier and speaker. I thought this was pretty neat but the frequency response was miserable and the range was just tens of feet so I did some library research and came up with the idea to use an ultraviolet glow lamp and a photomultiplier tube to improve both the range and fidelity of my light communication system.
The transmitter used an argon glow lamp purchased from Allied Radio and I had a Knight Kit signal tracer which provided the HV DC bias for the lamp and the amplifying function. A visit to a local garage's parts yard yielded a really nice car spotlight with a large mirrored surface parabolic reflector into which I mounted the glow lamp. The transmitter was easy, now on the the receiver.
This was not so easy but my research led me to select a 931-A photomultiplier tube because it was sensitive to UV light in the range of that emitted by the argon lamp. It set me back a couple of week's pay from my job but it was money well spent. For the 900 volts or thereabouts the tube required I used a salvaged TV power transformer and a 1B3 rectifier tube with the filament powered with a D cell. The phototube was so sensitive that I had to build a light shield with a long tube with pinholes in baffles to shield it from ambient light and to collimate and admit the UV from the transmitter. It worked very well and I was able to send the signal from a neighbor's house to mine in daylight over a distance of about 150 yards. I have no idea what the ultimate range was since I couldn't get more distant line of sight sites for testing. The audio was AM quality, limited by the ionization characteristics of the glow lamp, but it was tremendously better than that of the light bulb projects I had seen.
At the time I hadn't heard of Arthur C. Clark nor thought about using X-rays and that is probably good.
With the super bright LEDs and photo sensors available today this would be almost a trivial project which could be used to link to a part15 transmitter in the yard if one didn't want to run cables or use a RF link.
Neil