# How to calculate wide range?

Discussion in 'Wireless & RF Design' started by cpleng7, Oct 9, 2009.

1. ### cpleng7 Thread Starter Active Member

Dec 18, 2008
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Wide range is of the advantage of the AM circuit, can someone tell me how to calculate the range that AM wave can archive?

Beside wide range what else is advantage of the AM transmitter?

Apr 5, 2008
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3. ### cpleng7 Thread Starter Active Member

Dec 18, 2008
120
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is that the wavelength will be equal to the range of the wave to be transmitted?

Apr 5, 2008
15,806
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5. ### cpleng7 Thread Starter Active Member

Dec 18, 2008
120
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If I want to find the distance that the AM transmitter transmit, is that any formula to calculate?

6. ### Papabravo Expert

Feb 24, 2006
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There is no such formula that will produce the answer that you want.

7. ### wr8y Active Member

Sep 16, 2008
232
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What everyone is trying to say is that radio wave propagation has more to do with range than modulation method.

That means that the frequency you are on and power you are running determine range, not so much the method of modulation. Sure, CW or SSB are readable a LITTLE farther than AM or FM - but not much!

8. ### ELECTRONERD Senior Member

May 26, 2009
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There are many variables that will determine the outcome distance. Such as weather, propogation, and especially your enviorment.

9. ### wr8y Active Member

Sep 16, 2008
232
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I can see propagation, antenna configuration, weather and power - but ENVIRONMENT? What do you mean?

How are you using the term "environment"?

10. ### cpleng7 Thread Starter Active Member

Dec 18, 2008
120
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if i want to prove the AM can be transmit to the long distance, how should i do. Can someone tell me?

thank you

11. ### beenthere Retired Moderator

Apr 20, 2004
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In a situation where you ignore any other effect, use the transmitter output power. It attenuates with the square of the distance, but that can be calculated quite easily.

Assume some level of sensitivity at your receiver. When the antenna it is attached to receives that minimum level of power from the transmitter, then you are at the maximum range.

As you can see, the transmitter power out and the receiver sensitivity plus receive antenna gain all affect your calculation. Amateur radio groups have managed to get a signal transmitted at a 1 watt level and bounced off the moon - about 500,000 miles for that signal path.

12. ### cpleng7 Thread Starter Active Member

Dec 18, 2008
120
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why the scientist quite sure the AM is wide range than FM?