another radio question. Receiving stations far, far away

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Thanks for all the replies re: valve vs solid state radios
There was some very interesting reading and I learnt
quite a lot in that thread.

I have another question

I mentioned one of the radios I had was a transistorized
table radio. Well this also is a portable radio in that
it can be run via D size batteries.

Question is how far a signal have you ever received on a
portable AM band radio.  Some nights, especially in the
colder weather for some reason I can get stations like
2DU in Dubbo on the radio.  Can't explain why it works
more in the colder weather but it does. And the station
comes in well enough that you can hear it over all the
background noise.

This too considering I am in SA in Adelaide.

So with that in mind how far has anyone picked up a
radio station.

Re: another radio question. Receiving stations far, far away



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**You need to do a bit of book learnin'. Go investigate what you SHOULD have
learned in school, about 'The Ionosphere'.

For the record, I have picked up the following:

* Russia. On an ancient Panasonic Short Wave radio.
* Sydney radio, on a REALLY old HMV (leather covered, steel chassis)
transistor radio, out near Grenfell, NSW.
* 2WS-FM down in Queanbeyan (near Canberra).


--
Trevor Wilson
www.rageaudio.com.au



Re: another radio question. Receiving stations far, far away


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Radio Moscow - Russia
Radio Austria
Swiss Radio International
Vatican Radio
Radio Canada

ummm - lots more..

It's all to do with propagation - radio signals bouncing off the ionosphere
and back to earth many hundreds or thousands of kilometres away.  Different
seasons and times of day produce different propagation characteristics
across the radio frequency spectrum.  Sun spot activity also affects
propagation...

Look up propagation of radio signals and you will soon learn why it all
happens, how to make the most of it, and even how to predict it to some
extent!



Re: another radio question. Receiving stations far, far away



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But I'm talking AM receivers here.  Aren't the stations you
mention short wave?




Re: another radio question. Receiving stations far, far away



"Kate Fights, I Cry"
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** Well said  KFIC  -   and absolutely correct.

The AM band ends at 1700 kHz  -  just where the short wave band begins.

As a long time resident of Sydney I can say that it is (or was) very
possible to hear several AM band transmissions originating in New Zealand
whenever suitable atmospheric conditions prevailed, late at night on a
modest radio.

The suonds sheep bleating was unmistakable.





..........    Phil




Re: another radio question. Receiving stations far, far away




Phil Allison wrote:

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Some evnins youse can 'ear Helun Clak speakin loud
acruss the Tasmin, frum NZ Parlimint.

Evun the shiip are nervus around her.

Patrick Turner.

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Re: another radio question. Receiving stations far, far away



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Just for PA . Seems very appropriate

--
The difference between intelligence and stupidity is that intelligence
has its limits.

Re: another radio question. Receiving stations far, far away




"Kate Fights, I Cry" wrote:

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Its hard not to drift off topic to SW.

But there is a lot to learn about MW or the 550kHz to 1650 kHz band.

Patrick Turner.



Re: another radio question. Receiving stations far, far away


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[SNIP]

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As I said:

It's all to do with propagation - radio signals bouncing off the ionosphere
and back to earth many hundreds or thousands of kilometres away.  Different
seasons and times of day produce different propagation characteristics
across the radio frequency spectrum.  Sun spot activity also affects
propagation...

Different frequencies are affected in various ways by the ionosphere,
sunspot activity, season, etc.  AM broadcast band is at the bottom end of
what many call "shortwave" and the lowest Australian Amateur Radio band is
at 1800kHz, just above the AM broadcast band.

The concept of propagation remains true whether we are talking about AM
broadcast, LW (long wave - below the AM band) or SW (short wave - above the
AM band).  The only difference is how the actual frequencies behave under
certain conditions....





Re: another radio question. Receiving stations far, far away



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Point of confusion: Most broadcast MW and SW stations
use amplitude modulation, aka AM.  Though most people
will think of the MW broadcast band when "AM radio"
is mentioned.  But strictly speaking, a SW radio
that can hear an amplitude modulated SW broadcast is
an "AM receiver".

More precisely the OP wanted to ask "How far away was the
furthest MW broadcast radio station you have ever
received?"  For myself, I picked up a station in Iowa
while listening in NJ.  That's a bit less than 2000km.
But remember that the USA's MW broadcast band is rather
crowded, thus blotting out further distance reception.
Many frequencies here you get small islands of service
in a sea of interference.

Re: another radio question. Receiving stations far, far away



"robert casey"

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** The OP was clear and very specific:

 " Question is how far a signal have you ever received on a
portable AM band radio.  "


 Shame how many folk do not read as carefully.




.............      Phil



Re: another radio question. Receiving stations far, far away


On Fri, 13 May 2005 23:59:56 +0930, "Kate Fights, I Cry"

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Short wave IS AM. I've received Australian radio stations here in
England quite often. And generally about once a year we suffer
co-channel interference on TV from South Africa.

d


Pearce Consulting
http://www.pearce.uk.com

Re: another radio question. Receiving stations far, far away



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From a place called Mt. Helena about 30km east of Perth I used to pick up
Sydney, Adelaide, Queensland, numerous asian AM radio and on the odd
occasion US and European commercial AM stations at night on my Toshiba
multiband receiver. I also picked up on my old B/W portable TV GWN channel 3
(as it was then before it went statewide) from Bunbury about 300km away and
also Channel 11 in Geraldton well over 500km away.

One particular night I picked up channel 0, QTV from Queensland for a few
hours and it was quite watchable.

The TV was a B/W National portable transistorised model with a single VHF
rotary tuner and using only the indoor antenna that was attached to the back
of it. I can't really explain why this particular set picked these stations
up because my parent's set in the lounge with the external antenna received
nothing.

Ironically neither set received the local Perth stations very well because
we were on the wrong side of a slight hill.  I still have the portable TV...


Regards,

Clockmeister.








Re: another radio question. Receiving stations far, far away




"Kate Fights, I Cry" wrote:

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We had 2XX here in Canberra on 1,008 kHz, same as 2AD in Tasmania,
and that could be heard in the background sometimes, since 2XX
was only 300 watts. Now they have moved to FM, and a sport station
with races is there, with zero fidelity, offering odds on chances of
losing all yer dough.

I have often heard Queensland stations here, and it depends on
ionosphere refelections etc, and I am at a loss to
explainn further, but should you be able to erect a long enough antenna
with a length ideal for the broadcast band, preferably with an L plan
shape,
then the two antenna signals can be phase adjusted to prefer the station
you want.

It won't be hi-fi.

But the trouble is most stations are same old boring stuff you get from
the city stations since they
have networked them all.

For short wave, a rotating beam antenna like what the ham radio guys use
is quite good but
their beams favour 7, 14, 28, 56 MHz.
So maybe you shouls tudy the old books about radio wave propagation and
antennas; many books are devoted just to antennas.

If you have a non resonant long wire antenna just thrown over the roof
and running in through a window to your set,
then its wise to make a good earth for the set, since the antenna signal

needs a *circuit*, so electrons can move from antenna to ground and back

One can also use an inductor to earth, then a series tuning capacitor to
the antenna,
and take the radio signal from the inductor. The capacitor is then tuned
so the antenna
and cap and inductor make a resonant circuit and this often boosts the
signal you want
with others close by maybe 15 dB. Noise outside this band will be
rejected.

MW and SW depends a lot on antennas. Ask any ham.

I have to help a ham operator lower one antenna and raise another
tomorrow.

The beam we are taking down has 4 rods or 9 metres long each, quite a
beast.

Radio interest was real big in the 1950s, when
guys built all their own gear.
Now they buy at DSE and plug and play,
or they use a "virtual" receiver that appears on a PC screen
so the maouse can be used to alter RF gain noise filtering, selectivity,

band filtering, side band, et all.
This approach simply digitisers the RF input signal and
counts what comes in, then a program is applied to decode the data.

The radio waves are still there but today's latest receivers are very
different to what they were
up to the age of the PC.

Still, I have several old 7 tube communications sets I'd like to restore

that an old ham left to me when he passed away a few years back..
They would have gone to the tip otherwise.
They can still give pretty good performance, and its possible to add
digital processing to clean up speach signals.

Nothing here may be of much interest to hi-fi folks but the old ham I
knew
was very interested in the lo-fi side of ham and talking to old mates in
the UK
as well as what he could get from his sound system.

To know more about radio, you have to read books and do experiments.

Patrick Turner




n the very old days I used to regularly listen to


On Fri, 13 May 2005 19:24:01 +0930, "Kate Fights, I Cry"
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In the very old days I used to regularly listen to JJ in out of Sydney
on an old AM radio in my shed  most nights in Melbourne.
..
Francis Xavier Holden

Re: another radio question. Receiving stations far, far away



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On shortwave, you can hear stations from halfway around the
planet.  But I assume that you are asking about the 1MHz
MW AM broadcast band.  The farthest station I've picked up
here in New Jersey (next to New York City) was about 1200
miles, or about 2 Megameters (2000km) distant.  That's about
halfway across the USA.

Re: another radio question. Receiving stations far, far away


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I used to have a set that would pick up 3/4 of the way around the planet...

Re: another radio question. Receiving stations far, far away


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Okay...  But halfway around the planet from NJ puts you just
off the western end of Australia.  Every other point in the world
is closer.  ;-)

Re: another radio question. Receiving stations far, far away


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To state the bloody obvious. Americans...

Re: another radio question. Receiving stations far, far away


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Might be long path .wawawa

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