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by TheAmazingIdiot 5285 days ago
Comments like yours is why I didn't post my callsign.

We've discussed what my proposal was with the 2 local ham groups. One person works for the FCC and finds non-compliant stations. From what he indicated, as long as I put "EXPERIMENTAL" on the device, and watch for interference (iow: be a good amateur operator), I can do this.

I've passed their kind requests, along with publishing what I am doing and with what wattage I am transmitting. I am also monitoring my emissions as I usually do when operating.

I'd also like to remind you that an evil device called a microwave oven transmits more as static on 2.4GHz broadband than my narrowband wifi.

1 comments

You can think what you like, of course. You're still intentionally generating OOB emissions. HAMs like you are actually dangerous to the hobby.

A U.S. Federal Standard exists (and is used in most of the world), that limits the amount of microwaves that can leak from an oven throughout its lifetime to 5 milliwatts of microwave radiation per square centimeter at approximately 5 cm (2 in) from the surface of the oven after sale. (at manufacture, the limit is 1 mW/cm2 at 5 cm.)

US Dept. of HEW, FDA, Bureau of Radiological Health, “Regulations and Enforcement of Radiation Control for Health and Safety Act of 1968” paragraph 1030.10; Microwave Ovens pp 36-37 PHEW Publication No. (FDA) 75- 8003, July 1974

Now, what's the EIRP of your setup again? Assuming a 50mW (17dBm) radio and 2.2dBi 'short dipole' antennas, and maybe 1dBm of loss in the connectors/coax, you're at 18.2dBm EIRP at the surface of the antenna. Call it 65mW for grins.

At 2450MHz, you'll be down -14.2dB 5cm away. 18.2-14.2 = 4dBm, so 2.5dmW @ 5cm. You're lower than a worst-case microwave (but higher than anything that's allowed to be sold!), unless you fit high-gain antennas or high-power radios.

KD5FGA, btw. (also www.netgate.com)