Ham Radio

@lynlynch I know bluetooth band is unlicenced globally its around 2.4GHZ but power is limited to 100mW. can you tell the possible minimum value of power and frequency for maximum range of communication. If you dont know... its fine. just leave it.

maximum range of communication

There are two ends of the communication channel: the transmitter side and the receiver side. If you want to increase the range you should either increase the transmitted power (this is the "easier" way)or increase the receiver sensitivity (This is much more harder). Or, the third way, build better antenna. Antennae can virtually increase the transmission power to a selected direction, or increase the level of received signal from that direction. In addition, the wave propagation depends on the time of day and the high atmospheric meteorological conditions.

73,

HA5YAR

on some frequencies its possible to to use qrp ie very low power say 80mw

or you could try EME

Try googling it

http://www.google.co.uk/search?q=low+power+qrp&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&rlz=1I7GGLT_en&redir_esc=&ei=tLXuTJCwFYaAhAer5eTpCw

http://www.google.co.uk/search?q=best+frequencies+for+low+power+qrp&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&rlz=1I7GGLT_en&redir_esc=&ei=6rXuTOLkH4-zhAe3gbGhDA

http://en.wikipedia.org/wiki/EME_(communications)

peterg7lyq

EME

better link

http://www.google.co.uk/search?q=earth+moon+earth+communication&sourceid=ie7&rls=com.microsoft:en-gb:IE-SearchBox&ie=&oe=&rlz=1I7GGLT_en&redir_esc=&ei=aLbuTMGEAsGKhQfr4vHFDA

peterg7lyq

I just couldn't help myself.

You can get more information about HAM Radio by visiting following websites:-

http://www.arrl.org/ http://www.QRZ.com

Wish you all the best...

You can get more information about Ham Radio by surfing following websites:

http://www.arrl.org/ http://www.qrz.com/

wish you all the best in your research... ... ...

Yes you can. To do so you will use frequencies between about 3 and 20 mHz since these frequencies bounce off the ionosphere and are propagated over the horizon. You cannot use higher frequencies since above 30 or so mHz the radio waves penetrate the ionosphere and go into space so only line of site communication is possible. Power is not critical. Five to 100 watts would do it under the right conditions. 1000 watts gets you into a more reliable realm. Also it is very variable due to sunspot activity which affects the ionosphere. I believe we are in a period of high sunspot activity so that is good for long range "skip".

My friend is a Ham and I overheard him talking to someone on the west coast of America from his locations at ± 26S 28E (the closest he could manage to the other side)

The communication however depends heavily on conditions of the ionosphere, magnetic etc on that day and hour.

I believe tuning the antenna properly would also improve the chances.

Hello Hendrik is it possible to communicate from extreme ends of earth?

Yes

The extreme end from my location is somewhere in the ocean and Mr Neptune do not owe a Ham radio.

Yes, it is possible.

You will require at least 100 Watts of RF power into a directional antenna, preferably a quad antenna. The frequency is the 14 Mhz band. If you can pickup signals from those locations, you can surely reach them. First listen for the signal.

I have a Ham Radio fan as a friend, and although I have not asked him specifically about this, I know that he "travels" with his radio all over Europe via "Repeaters". His radio does not even have a huge power output, its even handheld.....

I do not know what the true "distance" such links achieve are or how many repeaters you can get "up" in a particular direction, but that would also appear to be a "way to go".....

Maybe someone with better specific info on repeaters could chime in and clear that up?

Using repeaters/parrots is not a real HAM activity.

Using factory-made rigs is also not a real HAM activity.

Build your own rig, use meteor-scatter connections, ect., and you will realize the taste of your own power...

In winter nights you can abridge 4-5000 km with 20-25 Watts on 80 meter band.

I am personally of the opinion that some Hams build their own gear, some Hams use repeaters, but not all.

It would appear that you personally possess nothing bought........ Your choice in the matter.....

But they are still called Hams.......even with bought equipment in the real world.....

Try reading the following link, you will understand many points far better I feel:-

http://en.wikipedia.org/wiki/Ham_radio

Here is a picture from that link showing quite clearly that a lot of "bought" equipment is often used, together with some seemingly "home made" stuff.

Guessing from the picture, more than half/most is "bought" equipment....also not forgetting the PC and screen etc. also bought not made, this under the definition of Ham or Amateur Radio.....:-

Quoting from the Wiki link:-

Ham Radio

Amateur radio, often called ham radio, is both a hobby and a service in which participants, called "hams", use various types of radio communications equipment to communicate with other radio amateurs for public services, recreation and self-training.^[1] Amateur radio operation is licensed by an appropriate government entity (for example, by the Federal Communications Commission in the United States^[2]) as coordinated through the International Telecommunication Union.^[3]

No mention in the name definition here of HAVING TO BUILD YOUR OWN EQUIPMENT just to be called a Ham!!!......

Later on it is mentioned under:-

Privileges

Unlike other RF spectrum users, radio amateurs may build or modify transmitting equipment for their own use within the amateur spectrum without the need to obtain government certification of the equipment.^[28][29]

Repeaters

These requirements also effectively limit the signal range to between 20 and 60 miles (30 km–100 km), however, the use of linked repeater systems can allow transmissions across hundreds of miles.^[15]

These repeaters, or automated relay stations, are used on VHF and higher frequencies to increase signal range. Repeaters are usually located on top of a mountain, hill or tall building, and allow operators to communicate over hundreds of square miles using a low power hand-held transceiver. Repeaters can also be linked together by use of other amateur radio bands, landline or the Internet.

Communication satellites called OSCARs (Orbiting Satellite Carrying Amateur Radio) can be accessed, some using a hand-held transceiver (HT), even, at times, using the factory "rubber duck" antenna.^[16] Hams also use the moon, the aurora Borealis, and the ionized trails of meteors as reflectors of radio waves.^[17] Hams are also often able to make contact with the International Space Station (ISS),^[18] as many astronauts and cosmonauts are licensed as amateur radio operators.^[19]

I feel that this post has cleared up any misunderstanding you may have over the definition of the name "Ham" and his usage of certain equipment types and repeaters quite nicely, I do hope you agree.....

I would also like to thank you in that by answering my original query in such a snooty unfriendly manner, you prompted me to have a look around for myself on the web!

And look what I found!!

Have a great day in spite of me!!

(Any day that goes by without me learning something new is not such a good day.)

Therefore today was BRILLIANT!!!

Hi Andy,

I've been a licenced HAM since 1968 so I'm fairly familiar with the possibilities but I think being a HAM means to explore the joy of building rigs, using them to establish connections, to enjoy the feeling you are able to abridge large distances without using the expensive official infrastructure.

Buying a factory-made rig and using it via repeaters is very similar to using a GSM phone...

...and your point is?

Although I do feel/agree with you that many GSM users should be heavily tested (and should pass an exam) before they can buy one....which they don't at this time....it would stop the simple folk annoying so many people every day. Totally with you on that point!!

Therefore your analogy is completely false. GSM is something else....its just telephones without wires...

The same as your Ham definition was incorrect.......

Even using a CB rig here needs a license from the government before you can switch on....no exam though......

So using a GSM telephone requires even less formalities (and intelligence in passing exams) than both Ham & CB equipment ......

Ham Radio users are generally (there are exceptions of course to any rule!) intelligent people who take their hobby seriously and have widespread friends.......

Sometimes they are people who for one reason or another, cannot get out and talk to people on the street etc.. Physically handicapped or similar.......

All the Hams I have personally met and known except one (not you, a neighbour in the UK many years ago!) were top notch people.......well above average in most human attributes.....therefore it appears to be a good hobby for most people's character in my lowly opinion.......maybe some of it will eventually rub off......

From Wikipedia:

The Kennelly–Heaviside layer, named after Arthur Edwin Kennelly and Oliver Heaviside, also known as the E region or simply the Heaviside layer, is a layer of ionised gas occurring between roughly 90–150 km (56–93 mi) above the ground — one of several layers in the Earth's ionosphere. It reflects medium-frequency radio waves, and because of this reflection radio waves can be propagated beyond the horizon.

Theoretically, you could receive your own signal with some delay.

And then there is amateur satellite radio: http://www.hobbyspace.com/Radio/index.html

Amateur radio operators have been known to maintain communication when all other means are not possible. There was/is? the M.A.R.S. (Military Affiliate Radio System) that I used when I was in the USN. to talk to my family. The Ham operators graciously volunteered to allow me into their homes to link up and phone patch from one part of the world to another. They paid the long distance phone charges out of their own pockets.

Theoretically, you could receive your own signal with some delay.

Not only theoretically, but if you work on CW and you have a good receiver with short recovery delay, after transmission you can hear some of last fractions of your transmission with a 0.2 - 0.4 sec delay.

The answer to your first question is yes.

To be allowed to use those bands are required to get a licence. Now, the good news is : Getting a licence will provide all the answers to the questions that you currently have, has well as to the very numerous questions you will have in the future.

It is quite easy to prepare yourself to the exam using guides that are widely available (you will find plenty of links from the previous threads).

Have fun ! This can remain quite easy but you can make it as technically challenging as you want it to be.

This link shows the US ham bands. I understand that the 6 meter and 2 meter bands use repeaters because they are line-of-site otherwise which limits the distance to <100 miles or so. You may be asked to make a donation to use the repeaters. I have a friend who uses a satellite (frequencies are in the GHz). I think transmit and receive use different frequencies to prevent feedback in the satellite.

OSCAR (Orbiting Satellite Carrying Amateur Radio) satellites work with frequency/band shifting. There is about 10 MHz shift between uplink and downlink frequencies in the 2 meter band (early satellites used to use the 10 meter band too). You must also calculate with the Doppler-effect.

I want to point out that Hams (for the most part) are the greatest batch of people I have known, and I have been involved in ham radio for almost 54 years.

Check with www.arrl.org They can possibly help you find a ham club in your area. Hams love to help people get into the hobby. ARRL also publishes all sorts of literature on the subject. Note though that ARRL is appropriate for the US. Other countries have different systems for licensing.

Get your license and come join the party.

Bill NW7L <-my call

I am not a Ham radio enthusiast, but I generally like the people that do. I have several friends who are active Hams.....

I agree with your comments in that area completely......

With a 90 ft log-periodic antenna, or 3 wavelength rhombic antenna, you could communicate with 300 milliWatts, but with a piece of wet string it might require a Californian kiloWatt. Stay below 28MHz.

Would you believe... we have our own Internet?? Well, much like Internet only it is radio based.

During a local emergency, the phone lines were swamped. Most likely "Yes aunt Lilly, we are OK, but since you are here... jabber... jabber... jabber... etc." With no phone lines available, there was no Internet. Local Red Cross had important information they had to get to their National Headquarters so we put it on the packet radio network. The info got to Washington DC and Local Red Cross had a reply back in about 15 minutes. They were quite impressed.

One sub-group in ham radio is ARES or Amateur Radio Emergency Services. These people train to handle emergency communications and are ready to go at the drop of a hat. AND IT IS ALL FREE!! Hams are not allowed to accept compensation for their services.

Another example... a few years ago, we had some severe forest fires, and fire crews were called in from all over the state. They discovered that when they left their local areas, their radios no longer worked. Their repeaters were still on their mountain tops at home. We hams provided communications for them and got the job done.

Enough of this for now.

Bill NW7L

Very interesting and informative.....thanks.

In 1972 there was a terrible flood in North-Eastern Hungary (HAM districts HA6-9-0). The official communication system collapsed so we gave a voluntary radio grid in order to transmit/relay the necessary information...

73,

Laci HA5YAR

It just goes to show that hams all over the world are good people.

Bill NW7L