Thanks to YouTuber Tom Scott, we have a glimpse into something quite interesting to hams. The Green Bank Telescope sits in the United States National Radio Quiet Zone (NRQZ) is a roughly 100 mile2 area where radio communications fall under stricter operating guidelines. The area is not as intense as it sounds, however, operators in the area should note the following from the ITU-R RA.2259:
NRQZ thresholds for coordination exist at all frequencies. Within protected radio astronomy bands, the threshold for coordination is that given in Recommendation ITU-R RA.769. Outside those bands, the threshold level is given as a function of frequency. Based on a 20 kHz measurement bandwidth, the calculated power density of the transmitter at the reference point should be less than
- 1 × 10–8 W/m2 for frequencies below 54 MHz
- 1 × 10–12 W/m2 for frequencies from 54 MHz to 108 MHz
- 1 × 10–14 W/m2 for frequencies from 108 MHz to 470 MHz
- 1 × 10–17 W/m2 for frequencies from 470 MHz to 1 000 MHz
- freq 2 (in GHz) × 10–17 W/m2 for frequencies above 1 000 MHz
All amateur radio stations are excluded within a 10 mile radius [of the telescope], with the exception of repeaters and beacon station modifications or installations.
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