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Old 17th November 2012, 02:36 AM   #31
freax is offline freax  Australia
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Quote:
Originally Posted by sco1t View Post
the laws are not that strict on radio transmitters in the uk, if they were how could they sell these small fm transmitters in the most uk shops Buy Belkin Tune FM Transmitter at Argos.co.uk - Your Online Shop for MP3 accessories.
they transmit over 10 meters ?

and there is worse I could be doing then transmitting Womack and Womack for over 2 meters of air to a 1950's radio :P
You can also buy them off eBay for a fraction of what Belkin charge you.
Their power output is so low and so well controlled (by transistor) that they are practically legal contraband, but no ham radio operator would endorse them.
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Old 17th November 2012, 02:37 AM   #32
sco1t is offline sco1t  United Kingdom
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CB radio is free for up to 5 Watt
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Old 17th November 2012, 02:40 AM   #33
freax is offline freax  Australia
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Radio Electronics: Amplitude Modulator (AM) - For Dummies
http://sci-toys.com/scitoys/scitoys/...ansmitter.html

Build this and get back to us, its simplicity is what keeps it safe, and if it does your job then walla, problem solved, case closed, thread shut, and we can all stop having heart attacks.

Its got a very limited range but I bet that with a large enough receiving antenna on your radio you should be able to pick it up over a few meters.

Just don't hookup the radio antenna and this little transmitter's antenna, that might cause bad things to happen.
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Old 17th November 2012, 02:43 AM   #34
sco1t is offline sco1t  United Kingdom
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so you're saying I can't connect that to a huge 1000 watt valve??? the uk is so unfair :'( lol
joke :-)
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Old 17th November 2012, 02:48 AM   #35
freax is offline freax  Australia
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Originally Posted by sco1t View Post
so you're saying I can't connect that to a huge 1000 watt valve??? the uk is so unfair :'( lol
joke :-)
Nevermind 1,000 watts, try a 1megawatt water pool cooled super mega transmitter thats got a direct link to the power station :P

http://www.youtube.com/watch?v=7WXZ2T2fosw

to get guaranteed worldwide coverage you need at least 250kW anyway, 500kW is best, and you know what they use? transistors, know why? cause tubes have to dissipate 50% of their output power in the form of heat (hence the need for large enormous water pools outside with fountains that air-cool the water)

Might want to try this too: AM transmitter with TL072 - YouTube

Click the image to open in full size.
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Last edited by freax; 17th November 2012 at 02:51 AM.
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Old 17th November 2012, 02:53 AM   #36
sco1t is offline sco1t  United Kingdom
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how long would it take the police to come if I transmitted over the uk's number 1 radio station at 1megawatt? lol
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Old 17th November 2012, 02:59 AM   #37
freax is offline freax  Australia
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hmm, accounting for them adjusting for power levels (a knob on their direction finder), 5-30 minutes.

However them getting a court order to knock down the door to your house, possibly anywhere from a few hours to a day.

They wouldn't really need a direction finder though, all they would need to do is look out for the bloke with the house with the bright green flourescent glowing lawn.

Which is supposedly what happened with nikola tesla's lawn so many years ago, st elmo's fire...

Exceptionally dangerous stuff RF is, one touch and it can burn a hole right through your finger and out the other side, like a bullet.

To top it off it can jump across a room to get at the pen in your top pocket on a whim.

Hence the use of large, barbed wire fences that surround radio transmitter towers.
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Last edited by freax; 17th November 2012 at 03:04 AM.
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Old 17th November 2012, 03:28 AM   #38
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Originally Posted by sco1t View Post
how long would it take the police to come if I transmitted over the uk's number 1 radio station at 1megawatt? lol
I get the impression that you don't take the legal issues very seriously, but with so little knowledge of electronics an output of any appreciable power is likely to be smeared across a large chunk of the spectrum, potentially causing nuisance to thousands or more users and possibly interfering with essential services, such as air traffic control.

How long do you think it would take some aggrieved parent with a shotgun to find you if you caused the death of their children?
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Old 17th November 2012, 03:50 AM   #39
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Mr culture, I get the impression that you don't take know a "joke" when you see one and yes I do know about air traffic that's why I picked shortwave. In the uk there is no shortwave or long wave radio stations any more just an empty band. I will be transmitting at about 0.01 watt so stop over reacting about nothing!!!! you sound crazy .....
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Old 17th November 2012, 03:53 AM   #40
sco1t is offline sco1t  United Kingdom
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and the transmitter output will be checked and tested,, shhhhhhh
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