https://sudoroom.org/mediawiki/index.php?title=Mesh/Decentralized_FM/AM_radio&feed=atom&action=historyMesh/Decentralized FM/AM radio - Revision history2024-03-29T09:16:30ZRevision history for this page on the wikiMediaWiki 1.37.2https://sudoroom.org/mediawiki/index.php?title=Mesh/Decentralized_FM/AM_radio&diff=9387&oldid=prevJuul at 04:31, 1 May 20152015-05-01T04:31:56Z<p></p>
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<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 21:31, 30 April 2015</td>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>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.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>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.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>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.</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>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<ins style="font-weight: bold; text-decoration: none;">,000 and if we can get them for $50 per unit then it's $30,000 to $75</ins>,000. Which puts it not entirely outside of the realm of possibility.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>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]. </div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>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]. </div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br/></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>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.</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>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.</div></td></tr>
</table>Juulhttps://sudoroom.org/mediawiki/index.php?title=Mesh/Decentralized_FM/AM_radio&diff=9371&oldid=prevJuul: 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<p>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..."</p>
<p><b>New page</b></p><div><br />
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.<br />
<br />
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.<br />
<br />
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]. <br />
<br />
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.</div>Juul