Question about unrestricted bands
- Thread starter thrival
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N_Jay
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Look at the ISM (Industrial, Scientific, and Medical) bands.
But not sure there are any in that range.
You could get a ham license and use ham bands.
But not sure there are any in that range.
You could get a ham license and use ham bands.
SkipSanders
Silent Key
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There are no 'unrestricted' bands. There are only bands where you don't have to be licensed, but still must obey the rules about maximum power and other things.
Here's the rules:
http://www.access.gpo.gov/nara/cfr/waisidx_06/47cfr15_06.html
Here's the rules:
http://www.access.gpo.gov/nara/cfr/waisidx_06/47cfr15_06.html
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OK, I looked at those files and there's a lot to plow through. Could someone save
me some time and tell me what bands don't require a license? I just want to
use RF for power, not transmitting any content. I guess the HAMs and scanners
would call me 'noise.'
me some time and tell me what bands don't require a license? I just want to
use RF for power, not transmitting any content. I guess the HAMs and scanners
would call me 'noise.'
I guess this is the most confusing part of your need. I don't know of any band that doesn't have some kind of communications in it. That is why Part 15 devices have such restrictions on them. If you are going to run any "power" at all, then what you are looking for doesn't exist.thrival said:
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N_Jay
Guest
thrival said:
What is this for?
Work? School? Personal research?
Seems you are asking for someone to do your work for you?:roll:
Don_Burke
Member
There are non-licensed bands all over the place, but most have pretty severe power restrictions.thrival said:
The only frequency I can think of right now that does not seem to have much in the way of rules is 27.120 MHz, right between CB channels 13 and 14. I have seen it used by plastic welders and have heard of plywood bonding machines that use it.
If you can come up with a ballpark frequency, maybe someone here can help you.
I dont know what kind of experimentation you are doing, but if your setup is small enough, maybe you could make a small faraday cage out of wire mesh. If the cage was made well enough and grounded, you could probably radiate quite a bit of power inside of it without disturbing anyone on the outside. I have no expeirence with it, but it seems plausible. Maybe someone who knows more about RF testing could offer some advice........
Slyster
Member
I'm curious to know what your attempting too!
Actually, there IS one truly unrestricted band.
Anything above 300 GHz (GigaHertz, not MegaHertz, mind you!!!) is fair game.
Have fun up there!
Exception: In the IR, visible light, and UV bands, output power is restricted by the FDA. (Laser devices.)
Elroy
Anything above 300 GHz (GigaHertz, not MegaHertz, mind you!!!) is fair game.
Have fun up there!
Exception: In the IR, visible light, and UV bands, output power is restricted by the FDA. (Laser devices.)
Elroy
First, I'm not looking for anyone to do my "work" for me, but I didn't think it 'work' for those
more knowledgeable on the subject, to inform me of frequencies they know about, where a
license isn't required.
I was thinking about 50 Mhz initially, but found the Radio Astronomy band just under 75 Mhz.
Point is to be somewhere w/sufficient power density and the traffic ain't, not cause too much
noise earthside. Directional antennaes pointed up hopefully wouldn't be bothered.
Intent is to run a car, about 150 watts. Under the hood, could act like a faraday cage. Hey
if my idea works maybe the feds would give me my own slice ;( not likely, I know.)
more knowledgeable on the subject, to inform me of frequencies they know about, where a
license isn't required.
I was thinking about 50 Mhz initially, but found the Radio Astronomy band just under 75 Mhz.
Point is to be somewhere w/sufficient power density and the traffic ain't, not cause too much
noise earthside. Directional antennaes pointed up hopefully wouldn't be bothered.
Intent is to run a car, about 150 watts. Under the hood, could act like a faraday cage. Hey
if my idea works maybe the feds would give me my own slice ;( not likely, I know.)
WP4MZR
Member
I'm still not clear on what you are trying to do, but all you need is a dummy load. If you have a ham radio license then just pick a non used frequency. Whatever you do, use a dummy load, don't be radiating unnecessary noise.
Don_Burke
Member
Communications is very much entrenched in that region, so this is indeed "work" to figure out.
I would say abandoning the idea of going unlicensed would be my first step.
50 MHz would no doubt give you problems with TV channel 2 and puts you on top of the 6 meter Amateur band.
Putting 150 watts at the receiver is going to involve an outrageous amount of power with current technology, so you have to come up with that power or come up with some new technology. Either way, your work is really cut out for you.
For development, an Amateur license would be the way I would go. 1000 watts will not get you 150 watts, but certainly could run something smaller, like a 1/28 or 1/10 car.
With the wireless digital people pouncing anywhere they can find frequencies, getting ITU to buy off on power transmission is going to be an uphill battle as that would take out the frequency used for a very large area. Proving the concept first will certainly help.
I would say abandoning the idea of going unlicensed would be my first step.
50 MHz would no doubt give you problems with TV channel 2 and puts you on top of the 6 meter Amateur band.
Putting 150 watts at the receiver is going to involve an outrageous amount of power with current technology, so you have to come up with that power or come up with some new technology. Either way, your work is really cut out for you.
For development, an Amateur license would be the way I would go. 1000 watts will not get you 150 watts, but certainly could run something smaller, like a 1/28 or 1/10 car.
With the wireless digital people pouncing anywhere they can find frequencies, getting ITU to buy off on power transmission is going to be an uphill battle as that would take out the frequency used for a very large area. Proving the concept first will certainly help.
thrival said:
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N_Jay
Guest
thrival said:
"Run a car" as in use the RF to do some type of work?
or are you talking about using a radio link for a remote control?
Don_Burke
Member
My understanding is that you are trying to transmit power to the vehicle to eliminate at least some of the weight of a storage battery.
If this is correct, a dummy load is not part of the solution.
If this is correct, a dummy load is not part of the solution.
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N_Jay
Guest
thrival said:
You are trying to use RF across the spark plug?
This has been long looked at. I think the guys at MSD, inc. have it down to a science.
http://www.msdignition.com/1ignitions.htm
You would need to feed the spark plug in a non-radiating manner. That would mean finding a way to characterise the impedance of the plug, and then design a source that is well matched.
Have fun, but I think some additional study is needed well before you worry about the frequency.
WP4MZR
Member
thrival said:
Love how this thread went from RF to Spark plugs...Thrival, you need to be more specific...
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