FCC and Exposure Limits

[W2VW]

What do you guys enter for average power in the online calculator for AM with our non-sine wave voices?

Shouldn't make any difference since area under the curve is same for positive and negative peak.

Now if someone purposely crunches the negative waveform things get difficult.

[K6JEK]

I'd just use 100% and work backwards.
klc

I guess my question is 100% of what, 1500 using the rule of thumb of 4x the 375 watt carrier?

[Steve - K4HX]

For AM, the duty cycle is 100% for the carrier power and the same as SSB for the PEP power. Example for a 100 watt output carrier:

Pave for carrier is 100 watts.
Pave for modulation is 400 watts and 0.2 duty cycle or 80 watts.
Pave total is 180 watts.

This is quite a different number than the 400 watts you would get using the 100% duty cycle given in the subject table.

I also did not include the amount of time transmitting in the above calculation. I did not include feedline loss since it would vary with each installation. So, these are worst case calculations. The linked site suggests the worst case for the 6 minute averaging period (transmitting 100% of the time). If you don't make old buzzards, it seems that number would be high.

It doesn't seem like it's "easy" to exceed the current limits, even on 10 meters. Running full legal limit AM and making old buzzards (100 percent transmit time), someone would have to be less than 16 feet from a dipole to be in an area exceeding the controlled environment limit.

Your neighbors are assumed to be in the uncontrolled environment. They would have to be really close, less than 35 feet. I don't see this happening too often. And these calculations are using the gain in the main lobe. If someone is on the ground, they aren't in the main lobe or at the peak. If you use the 30 minute averaging period, there will be further reduction of the average power, easily 50 percent unless you are really buzzarding! In this case, your neighbor would need to be in the main lobe and less than 25 feet from the dipole.

Running a typical 100 watt rig (Viking, DX-100, etc) the distances drop down to 8 and 18 feet for the worst case situations.

[w1vtp]

I believe this calculator will apply in the forseeable future.

http://web.paulbunyan.net/users/jcrisman/index.html

There is helpful information and a calculator that makes the evaluation where is required by present part 97 regulations.  Give it a spin.  As far as AM operation we work off the PEP levels.  If we are running high power we should be able to make those kind of measurements

Al

[Steve - K4HX]

That calculator applies now and has for some time.

"Effective January 1, 1998....."


http://web.paulbunyan.net/users/jcrisman/mpe1.htm

[w1vtp]

That calculator applies now and has for some time.

"Effective January 1, 1998....."


http://web.paulbunyan.net/users/jcrisman/mpe1.htm

Yep