| ▲ | Show HN: Formally verified FPGA watchdog for AM broadcast in unmanned tunnels(github.com) | |||||||||||||||||||
| 32 points by anonymoosestdnt 3 hours ago | 5 comments | ||||||||||||||||||||
| ▲ | jetrink an hour ago | parent | next [-] | |||||||||||||||||||
At first I thought the "unmanned tunnels" description was just a way to avoid broadcast regulator scrutiny, but it does look like it's genuinely designed to be used underground as part of an emergency alert system. That led me to "leaky feeders", a type of broadcast antenna used in mines and tunnels. | ||||||||||||||||||||
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| ▲ | davepage 23 minutes ago | parent | prev [-] | |||||||||||||||||||
Could obtain better quality at the higher channel counts by phase shifting the audio for each channel such that the modulation peaks do not exactly align for each (as they do now). Even inverting the audio for half the channels would help. | ||||||||||||||||||||