Juul at 04:31, 1 May 2015

2015-05-01T04:31:56Z

← Older revision		Revision as of 21:31, 30 April 2015
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	Legal FM transmitters are so low-powered in the US that it doesn't make sense to even try. Their effective range is something like 300 feet max. We'd need A LOT of these to make it work.		Legal FM transmitters are so low-powered in the US that it doesn't make sense to even try. Their effective range is something like 300 feet max. We'd need A LOT of these to make it work.

	AM radio seems like a better option (though the chance of someone randomly scanning their car radio and finding the channel is almost nil on AM). The range is something like 1/4 to 1/2 mile for a good legal transmitter. To completely cover the entire area of Oakland we'd maybe need somewhere between 600 and 1500 transmitters. If we could get a decent transmitter setup for maybe $200 per unit, then that's $120,000 to $300,000. Which puts it not entirely outside of the realm of possibility.		AM radio seems like a better option (though the chance of someone randomly scanning their car radio and finding the channel is almost nil on AM). The range is something like 1/4 to 1/2 mile for a good legal transmitter. To completely cover the entire area of Oakland we'd maybe need somewhere between 600 and 1500 transmitters. If we could get a decent transmitter setup for maybe $200 per unit, then that's $120,000 to $300,000 and if we can get them for $50 per unit then it's $30,000 to $75,000. Which puts it not entirely outside of the realm of possibility.

	The [http://www.am1000rangemaster.com/ rangemaster] is apparently a good legal AM transmitter. It's about $750 for the cheapest model though. Here's [http://www.am1000rangemaster.com/zerobeat.html some info on running a decentralized AM transmitter network].		The [http://www.am1000rangemaster.com/ rangemaster] is apparently a good legal AM transmitter. It's about $750 for the cheapest model though. Here's [http://www.am1000rangemaster.com/zerobeat.html some info on running a decentralized AM transmitter network].

	If we used e.g. a beagle bone black with a GPS for timing then it would be theoretically possible to generate a clock or control a PLL with the raspberry PI based on the GPS timing, thus ensuring that the carrier signal phases of all transmitters are synced.		If we used e.g. a beagle bone black with a GPS for timing then it would be theoretically possible to generate a clock or control a PLL with the raspberry PI based on the GPS timing, thus ensuring that the carrier signal phases of all transmitters are synced.

Juul: Created page with " Legal FM transmitters are so low-powered in the US that it doesn't make sense to even try. Their effective range is something like 300 feet max. We'd need A LOT of these to m..."

2015-04-19T02:52:49Z

Created page with " Legal FM transmitters are so low-powered in the US that it doesn't make sense to even try. Their effective range is something like 300 feet max. We'd need A LOT of these to m..."

New page

Legal FM transmitters are so low-powered in the US that it doesn't make sense to even try. Their effective range is something like 300 feet max. We'd need A LOT of these to make it work.

AM radio seems like a better option (though the chance of someone randomly scanning their car radio and finding the channel is almost nil on AM). The range is something like 1/4 to 1/2 mile for a good legal transmitter. To completely cover the entire area of Oakland we'd maybe need somewhere between 600 and 1500 transmitters. If we could get a decent transmitter setup for maybe $200 per unit, then that's $120,000 to $300,000. Which puts it not entirely outside of the realm of possibility.

The [http://www.am1000rangemaster.com/ rangemaster] is apparently a good legal AM transmitter. It's about $750 for the cheapest model though. Here's [http://www.am1000rangemaster.com/zerobeat.html some info on running a decentralized AM transmitter network].

If we used e.g. a beagle bone black with a GPS for timing then it would be theoretically possible to generate a clock or control a PLL with the raspberry PI based on the GPS timing, thus ensuring that the carrier signal phases of all transmitters are synced.

Mesh/Decentralized FM/AM radio - Revision history

Juul at 04:31, 1 May 2015

Juul: Created page with " Legal FM transmitters are so low-powered in the US that it doesn't make sense to even try. Their effective range is something like 300 feet max. We'd need A LOT of these to m..."