just build this: iTx - Tube AM Broadcast Transmitter Kit | eBay
Its safe, legal, and it won't give you a big nasty fine!
Also look at the 90v battery eliminator that is for sale in that eBay store. http://www.ebay.com.au/itm/90-Volt-...ioTelevision_Telephony_SM&hash=item27cc8bf5db
Ontop of that it doesn't put other peoples lives at risk.
Legally you cannot build a transmitter at all, not unless you are a technician class ham, know why that is? do you have a frequency counter? a spectrum analyzer? an oscilloscope? a swr meter? a dummy load? a all of these bits of equipment are /necessary/ to test your homebrew transmitter before it gets an antenna hooked up to it, ontop of that you could end up burning out component after component because the antenna isn't perfectly matched.
Don't use tubes, use either that kit, something that has been proven, tested, and relied upon, or use transistors.
If you are going to be a giddy goat and use tubes anyway then get this thread moved to the tubes section so the right people can have a gnaw at it and maybe recommend something that they know won't cause any harm to the shortwave bands.
Just click on the exclamation mark on the left hand side of any post /!\ and type in: hi, could I get this thread moved to the tubes section please? as it involves tubes Thank you.
Its safe, legal, and it won't give you a big nasty fine!
Also look at the 90v battery eliminator that is for sale in that eBay store. http://www.ebay.com.au/itm/90-Volt-...ioTelevision_Telephony_SM&hash=item27cc8bf5db
Ontop of that it doesn't put other peoples lives at risk.
Legally you cannot build a transmitter at all, not unless you are a technician class ham, know why that is? do you have a frequency counter? a spectrum analyzer? an oscilloscope? a swr meter? a dummy load? a all of these bits of equipment are /necessary/ to test your homebrew transmitter before it gets an antenna hooked up to it, ontop of that you could end up burning out component after component because the antenna isn't perfectly matched.
Don't use tubes, use either that kit, something that has been proven, tested, and relied upon, or use transistors.
If you are going to be a giddy goat and use tubes anyway then get this thread moved to the tubes section so the right people can have a gnaw at it and maybe recommend something that they know won't cause any harm to the shortwave bands.
Just click on the exclamation mark on the left hand side of any post /!\ and type in: hi, could I get this thread moved to the tubes section please? as it involves tubes Thank you.
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Indeed, hence the necessary caution needed over this thread.
It basically means that if you are buying it within the EU you must put it into a metal enclosure, including your radio and your house.
Man those laws are pretty strict huh.
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What I described above, is called "Grid bias". AC that the rube generates is rectified on it's grid and applied as a negative bias. Such a way it stabilizes level of AC that it generates. When anode modulation applied from anode of SE amp, the tube's transconductance changes with anode voltage following audio frequency modulating signal. That changes level of AC radio signal that it generates.
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
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
I think its about time you guys (everyone in the EU) start petitioning for free-range radio waves...
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
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.
Radio Electronics: Amplitude Modulator (AM) - For Dummies
http://sci-toys.com/scitoys/scitoys/radio/am_transmitter.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.
http://sci-toys.com/scitoys/scitoys/radio/am_transmitter.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.
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
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
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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.
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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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?
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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