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Participant

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Directional Frequency Transmitter

09/13/2009 11:56 AM

I am currently working on a directional high frequency transmitter (cellphone range). Seeing as how there are 4 frequency bands in the cell phone market I would need to oscillate between all four (and everything in between) with the ability to "jump" over a set frequency which my radio is set to receive and transmit on. Does anybody have any ideas on how I can achieve this all while still working on a 24v DC power supply (which is not a big restraint if more is needed)?

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Shadow
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This discussion was "closed" on 09/15/2009 12:02 PM. No new comments are allowed.
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#1

Re: Directional Frequency Transmitter

09/13/2009 12:00 PM

I'd wonder if anybody has any ideas about the legality of such a system. Sounds like either a jammer or an eavesdropper, to me. Both of which may not be legal, if you care.

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#3
In reply to #1

Re: Directional Frequency Transmitter

09/13/2009 6:06 PM

Fellow subscribers,

I am well aware of the legalities of such a device and did not post my question here for such responses. I was educated in mechanical engineering therefore only have a basic knowledge of electronics. I have searched for the existence of such devices and have attempted to gain further knowledge on the subject but this self education has only taken me so far. Therefore I have turned to this forum for assistance in furthering my project. Please keep responses on topic. Thank you.

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#4
In reply to #3

Re: Directional Frequency Transmitter

09/13/2009 6:15 PM

Thank you for the clarification. This will help me stay on topic in the future.

Your attempt, " to gain further knowledge on the subject" is admirable.

Bullshit!

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#5
In reply to #4

Re: Directional Frequency Transmitter

09/13/2009 7:44 PM

Shadow has provided me more details using my CR4 private mailbox and I am discussing the project there, which is possibly where the specifics of this thread should stay due to the specific military application nature of the project.

A similar topic was covered previously before on CR4

http://cr4.globalspec.com/thread/732

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#7
In reply to #1

Re: Directional Frequency Transmitter

09/14/2009 9:23 PM

Taking the OP's wording in the opening post...I would agree with your thoughts regards the legality of this issue...regardless of the OP's perceived attempt to get answering posts 'on topic'.

The "topic" as I understand it is regarding a portable power supply running on 24v to assist in producing a high power voltage required in producing the desired range the device requires to infiltrate a given cellphone and the mechanism required to alternate between several frequencies of choice...illegal in my view and reported to CR4 admin to decide the international legallity of this progressive issue.

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#8
In reply to #7

Re: Directional Frequency Transmitter

09/15/2009 9:06 AM

Yes, and how anybody with a grand total of three posts can be giving advice to anyone else on etiquette is damned arrogant, and self absorbed to boot!

Who does this jerk think he is?

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#2

Re: Directional Frequency Transmitter

09/13/2009 3:35 PM

I don't know what country you are in but you can forget it if you plan on building a transmitter working in any of the the cellphone frequency bands as this is illegal.

It is also highly likely that you would need a licence and test report to operate a transmitter even if you were operating in one of the unrestricted frequency bands. Refer to 47 CFR Part 15 (Radio device regulations) and the FCC or equivalent local radio spectrum management division for more information.

http://www.fcc.gov/oet/info/rules/

Radio frequency device approval is a very detailed and confusing area and it is by far the simplest and best option to buy an already approved complete radio frequency (RF) device or module that can be incorporated in a product or design.

eg - http://www.google.co.nz/search?hl=en&source=hp&q=radio+module&meta=&aq=f&oq=

What is the application?

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#6

Re: Directional Frequency Transmitter

09/14/2009 10:54 AM

There are probably twenty five signal generators on the market that would do what you are asking for. Older ones are available on the used market at bargain rates.

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Users who posted comments:

CraziestOzzy (1); jack of all trades (2); lyn (3); Shadow (1); WoodwardDL (1)

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