A question for Techies:
My GF told me about the NPR piece and we checked out their website and looked up more info, and just this weekend I was at a clearance store and bought a cheap shortwave receiver for $15. It came with a hand crank that will re-charge the ni-cad batteries!
But the reception seems weak in the shortwave bands. I slowly scanned through all the bands and could only pick up a signal maybe once or twice ber band. Is this due to the cheapness of my radio? Or is it because of my location in a radio rich neighborhoood in San Francisco?
What can be done to improve my reception? When I had a walkie talkie as a kid, we'd attach a copper wire to the antenna and run it up a tree. Will something like that work with shortwave?
My GF told me about the NPR piece and we checked out their website and looked up more info, and just this weekend I was at a clearance store and bought a cheap shortwave receiver for $15. It came with a hand crank that will re-charge the ni-cad batteries!
But the reception seems weak in the shortwave bands. I slowly scanned through all the bands and could only pick up a signal maybe once or twice ber band. Is this due to the cheapness of my radio? Or is it because of my location in a radio rich neighborhoood in San Francisco?
What can be done to improve my reception? When I had a walkie talkie as a kid, we'd attach a copper wire to the antenna and run it up a tree. Will something like that work with shortwave?
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Re: Cheap Shortwave Radios
Sat, February 12, 2005 - 8:47 PMI bought a 'shortwave antenna' for my vintage Hallicrafter radio and it helps quite a bit (though I have yet to even listen to the thing that much or find any numbers stations) - All it is is a fifty-foot piece o' wire, and it works best if you have room to stretch it out in a straight line (outside the window would be best) - Different radios have different reception though, so your radio might be bunkola...
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Re: Cheap Shortwave Radios
Tue, February 22, 2005 - 2:31 PMI just stumbled across this tribe...
I'm a shortwave listener from way back
alas, shortwave is a slowly dying thing, as
is ham radio for that matter, but there is still
a lot to listen to out there.
My current problem is that I live in high density
housing in the city, and not only is there electrical
noise from computers, cheap unliscenced power
supplies (those $3 cellphone chargers seem to
be the very worst offenders of all in my house)
and the high power of local AM/FM/HDTV transmitters
will render cheap shortwave radios (and for that
matter, cheap FM radios) all but useless.
GOOD radios will have tools to combat these
noise sources.
Front ends (the antenna circuitry)
that can withstand a strong local station without
"clipping" (the same distortion you hear when
you turn a small radio up too loud) and as
a result, creating false copies of the offender all
oover the dial...
Pulse noise filters like ANL (cheap) NB (good)
DSP (can be very good, almost a miracle cure)
can delete or at least reduce the BUZZZZZ from
power supply things.
Variable IF bandwidth and "passband offset"
controls (only on very expensive radios) can
help filter out offending signals as well.
If you live in the boonies, a cheap SW radio
may bring in some interesting things. But
for most of us, a good radio is needed.
Think $100 and up. Sangean makes several
decent radios in that price range. Do get one
with at least an ANL control and a WIDE/NARROW
selection. Any less is really not enough for
the city dweller. SONY makes some nice ones
with "syncronous detection" which combats
the fading problem of really long range signals
and whough they cost a little more than the
sangean, definatly worth it.
I prefer the Zenith Transoceanic R7000-2
As a portable, I love "analog tuning".
But those command a premium and the
7000-1 model has some flaws you want to
avoid. These haven't been made in 20+
years. Strictly eBaY stuff.
Consider getting an active antenna.
I paid $1400 once for a drake, but even it was
no match for the light dimmers in the house
(I eventually replaced all the dimmers)
As for the numbers transmissions, why are they
there if there is no cold war??
Simple. If there were no transmissions, and
all of a sudden they were to start up, then
"everyone" would know that something was up.
So those stations go on, regularly, even if they
have nothing to say. And they probably always
will.
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Re: Cheap Shortwave Radios
Tue, February 22, 2005 - 2:44 PMOh and as far as the numbers stations themselves?
Spooky, the first time you hear them I suppose.
For that matter, a lot of the noise out there is a little spooky
But all you'll hear is a feminine voice, in some language or another,
going
2 3 0 1 3 (pause) 4 4 2 6 7 (pause) and so on. It's not really
worth buying a shortwave to hear it.
What is more, BBC worldservice is now available on the internet.
As is Radio Nederland (these used to be the #1 and #2 stations,
but RN is nowadays pretty darn boring.
Radio Cuba plays the best music, Racous cuban singing and drumming and is probably worth a listen. Radio Taiwan is pretty
good. Radio Australia is sometimes interesting. The rest of the time
you need to be a fan of cricket/soccer (ugh) Radio Canada is really variable but easy to recieve especially on the weekend days in the 12-15MHz zone.
During the evenings, look between 5.9 and 10.2 MHz - that's
where the action is, in 3 bands. And some broadcasters that
are outside of the bands.
During the days, look in the 12-25 MHz region. In noisier areas,
generally best operation is at 15MHz and below.
The internet changed everything, and most of these are online now anyway, the romance is still there, and there are many many stations
I havent mentioned, but they need good equipment. (All the ones
I've mentioned have strong relay stations, some in the US even)
I suppose you should be made aware that international broadcasters who plan on sending broadcasts in english towards the US tend to do so mainly in the early evening hours. Save for the annoying religous broadcasters, including some big ones here in the bay area. (bleah)
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Unsu...
Re: Cheap Shortwave Radios
Tue, February 22, 2005 - 4:11 PMthanks for the great info mike. now I know why the cheap little grundig I picked up gets very little SW signal in the middle of san francisco. Perhaps I can try it out if I take it out of the city sometime. oh well. -
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Re: Cheap Shortwave Radios
Wed, February 23, 2005 - 11:43 AMI've got a handheld Grundig Yacht Boy and it doesn't pick up much. At first, I attributed this to all of my other electrical equipment as well as living in San Francisco, but I've traveled with it and had problems elsewhere. For example, it was hardly any better in picking up signals in the Florida Keys, which are much less densely populated. Yact Boy still had the buzzing sound even down there, away from computers and tv's.
Guess I'll get a better radio. -
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Re: Cheap Shortwave Radios
Wed, February 23, 2005 - 12:29 PMIf you hear buzzing then there is interference.
Probably from a local TV transmitter. (60 hz buzz)
Could be from wet or slightly defective power lines. (also 60 Hz buzz)
Could be from a gasoline engine (it will have an onvious sound however)
Could be from a switching power supply (the buzz will be "slower")
Note that a $100 sangean may not be up to the task of resisting this sort of interference. The zenith I use is very good and even it gets twinges of bleedthrough.
At my old job, located next to a nature preserve, I could take the radio out there and pull in lots of nice clean signal.
You can drive down the freeway to an unpopulated area, or a rest stop and try it there in the late afternoon possibly.
But indeed it's tough out there for shortwave radio these days of digital and near megawatt (!) HDTV transmitters.
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Re: Cheap Shortwave Radios
Wed, February 23, 2005 - 12:35 PMOh, there are two kinds of interference.
"in band" interference is from things like lamp dimmers, welding machines, brush type motors, some TVs, computers (especially with the shields or covers removed, or cheap and illegal non type accepted equipment that hasn't passed emmissions tests) - not much you can do about this, though a Automatic Noise Limiter/Noise Blanker or whatever can help with buzzing.
"out of band" interference is from things like TV transmitters (they only emit frequencies "of interest") and the like, and they cause problems from overloading, as I stated earlier.
I guess that covers everything :) kind of.
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Re: Cheap Shortwave Radios
Wed, August 2, 2006 - 5:26 PMi have a yachtboy 400 (the digital one) and i'm very pleased with it. it has all it needs (ssb, receives much, especially with the wire-antenna) and kicks the other handhelds i have - maybe a top-range sangean could top it.
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Re: Cheap Shortwave Radios
Sun, February 27, 2005 - 8:21 PMMike, you know too much. The black helicopters will be landing in your front yard soon.
Okay, so my bargain was not much of a bargain at all, as I suspected it might be. But I like the idea of stringing a 50 ft antenna on the roof (fortunately I live on the top floor of a very un-monitored building). I'll see if that has any effect. Hey, does anyone know if it makes any difference what direction the antenna points, or whether it is at an angle, or even staight up and down?
A friend once made an antenna out of an aluminum pole that he had bent to a specific length in order to pick up a particular station that was far away. does this theory apply to shortwave? Why do they call it shortwave if one needs a 50 ft antenna to receive it? -
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Re: Cheap Shortwave Radios
Mon, February 28, 2005 - 12:49 AMIt was short at the time...
It was some time before they could even get a radio to work above 30MHz. Making an oscillator go that fast took some thinkin' (and the oscillator is the heart of all transmitters and recievers)
Yes the direction does matter.
As a child in a home with a biiig yard I constructed a huge switchable rhomboid antenna. (think of a baseball diamond) and there was noticible improvement (this was a "steerable" antenna)
Noise is the BIG problem though.
So, just try to run it exactly 90degrees out of direction with the local power lines. (that will make the antenna tend to ignore the "near field" comming off of the thing).
Keep the wire as far away from all metal objects as you can.
Don't run the wire along side any other wires or gutters.
Two wires in parallel can transfer energy between them.
Two wires crossing at exactly 90 degrees can not.
Consider getting a trap, to filter out the unwanted TV/FM garbage out - universal radio probably has one. Probably for way too much money tho.
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Re: Cheap Shortwave Radios
Mon, February 28, 2005 - 12:54 AMThe hands down best "passive" shortwave antenna is the "tilted unsymmetrical bridge" which looks something like
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two wires strung between two supports one higher than the other, the signal taken off about .4 of the way along one side.
I'll wager that the tribe text editor mangles that.
no matter. just string a wire and see what happens :)
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Re: Cheap Shortwave Radios
Mon, February 28, 2005 - 12:54 AMyep, it mangled it.
if you care I can dig up a url, but since you probably don't care...
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