what is it?

[leighbus]

what is HF and shortwave radio? is it like citizen band or amature that you need a licence for? and is it any good?

[Finch]

It's worth it, do you have enough space for a large antenna? if so then it's even better.
HF radio is used by many users like the military, aviation, marine as a long distance radio as the signals usually bounce off the ionosphere down back to earth known as skipping, so it can be a reliable long distance communication system.
The band is also used by HAMs also for long distance communications. Many radio stations from around the globe use HF because they then can be heard from nearly anywhere providing the receiver has the right gear.
Sometimes even spies use HF for long distance communications but they have their own codes, sometimes known as number stations because they are just saying random numbers.
27MHz CB is in HF too.
There is much much more in HF, who knows what you will find?
-Alex

[leighbus]

Thanks mate. I thought 27mhz cb wasnt very good. Like crap distance or something like that. Was i wrong?

[Finch]

It depends on the conditions. If there is alot of sunspot activity, the ionosphere becomes ionised and signals can bounce off easily known as skipping, where as if there is little sunspot activity the radio waves can simply go through the ionosphere. So if the conditions are right, 27MHz CB can be very long distance form of communications.
-Alex

[Comint]

Thanks mate. I thought 27mhz cb wasnt very good. Like crap distance or something like that. Was i wrong?

In the view of the Regulatory Authorities (the ACMA in our case) both 27 MHz CB and UHF CB are 'Local'.

Years ago, I lived in Darwin, and it was not uncommon for the local CBers to talk to the Philippines, or to Sydney, on 27 MHz, but that was only in the Summer months.

--
Comint

[Scannersplitterguy]

Just to add to the great comments so far:

HF covers a relatively small frequency range of 2-30MHz. That's only 28 MHz! When you scan UHF or VHF, that 28MHz range is hardly anything to get excited about.
BUT, what makes HF exciting is the HUGE range of wavelengths you are dealing with.
At 2MHz, the wavelength is 150 metres! At 30 MHz it's only 10 metres.
What all this means is that the lower HF frequencies (say 2-15 MHz) can reliably travel huge distances.
The higher the frequency, typically the less distance it will travel when 'skip' isn't occuring.

I have a Yaesu HF receiver and a 'longwire' antenna on the roof.
Some of the stuff in AM mode from far-off countries is amazing to listen to.
Alot of amateurs use HF, also the RFDS, army and capital city airports.
It's quite interesting listening in on Air NZ or Air Nandi flights when they are still 1000's of kilometres from Australia. USB and LSB are always used for communications,



Cheers!

[Stretch]

Do you think HF will ever fade out until its no longer used??

[Finch]

Do you think HF will ever fade out until its no longer used??

Maybe, I guess as satellite communications evolve and it becomes cheaper and more reliable than HF as long distance communications then it will die out. But I think people like HAMs will never stop using it, even if other people stop using HF then HAMs will get the whole band to themselves.
I think HF will be around for a while.
-Alex

[Scannersplitterguy]

Do you think HF will ever fade out until its no longer used??

I hope that wasn't a pun!!

HF can cover the globe, regardless of the time of day or night.
Satellite coverage is influenced by factors like bad weather, the satellites postion above the earth and the low RF power output they usually have.
Most HF SSB radios produce 50 watts at least....ranging up to kilowatts (if you can afford the gear!).
The sheer power produced by AM shortwave stations (ie. 5-100,000 KW) can reach just about anywhere.

[Stretch]

Do you think HF will ever fade out until its no longer used??

I hope that wasn't a pun!!

Nah it wasn't but having re-read it I can see where you came from

[878ROB]

Thanks mate. I thought 27mhz cb wasnt very good. Like crap distance or something like that. Was i wrong?

27MHZ radio is great for long distance, my station master was setup only 6 - 7foot from the base to the ground, i could hear and talk to NSW and VIC when the skip was in, and the thing is i live in Capalaba and i class this place as a big hole in the ground. No good for uhf here only hf unless you got sh*tloads of money to spend on a massive tower, but then again you still need to abide by council regulations of fixed height antennas.

Over all 27MHZ is great. It has always taken me far.

Rob

[hotmetal1000]

Do you think HF will ever fade out until its no longer used??

Maybe, I guess as satellite communications evolve and it becomes cheaper and more reliable than HF as long distance communications then it will die out. But I think people like HAMs will never stop using it, even if other people stop using HF then HAMs will get the whole band to themselves.
I think HF will be around for a while.
-Alex

I don't think hf will ever die off completely for long distance communications. Satellites are a bit prone to solar flares.
http://earthobservatory.nasa.gov/Featur ... rmax_4.php

[leighbus]

ok so apparently 27mhz CB is pretty good when the skip is happening but whats the distaqnce like when theres no skip? and how often does the skip happen?

sorry for all the questions guys its just that im getting conflicting info from another part of this site. plus it interests me anyway.

[Finch]

About 10 to 15 ks on a AM CB no skip. A skip will only happen when there is enough sunspot activity.

[hotmetal1000]

Single side band about 40k's normal I suppose but from my location here I can talk to Brisbane quit easily of a night time about 100k's and talked to the Gold Coast as well.
When the skip is running all depends on the skip but normal from here is Victoria and South Aus. Skip doesn't only run when there is sunspots but is hugely increased by sunspot activity. During summer months you always get a bit of day time skip happening.

[878ROB]

I find everything use to come in during the late arvo and last right through out the evening.