#robotics Logs

Jul 25 2021

03:13 PM Malvolio is now known as Guest9161
03:50 PM gartt: If I had a raspberry pi in a weatherproof box on a high tree on a hill on my family's property which might be a bit over 1500 feet in a long strip, what's the best way to get basic data back (text data, maybe maximum of under a kilobyte) without requiring a subscription (cellular module or Iridium)? I was looking at xbee. Is there such a thing as using VHF with very low power legally?
04:06 PM Tom_L: XBee might be a good way to go if it has the range
04:08 PM Tom_L: there's a Thesis on it if you feel like wading thru it: https://digital.library.unt.edu/ark:/67531/metadc500182/m2/1/high_res_d/thesis.pdf
04:25 PM gartt: Tom_L: Thanks, reading now
04:27 PM gartt: If xbee didn't exist, what'd be the next most viable legal option? APRS isn't legal without a license, VHF I believe isn't legal for these uses - maybe CB radio but that's not viable due to being so crowded and limited
04:30 PM gartt: For example, since data being sent would be very small / very low bandwidth
04:31 PM gartt: The guy who wrote the paper seemed very happy with xbee though
07:08 PM mrdata: 'If xbee didn't exist'
07:09 PM mrdata: not sure about the requirements here
07:10 PM mrdata: whatever they are, i would go with off the shelf stuff
07:10 PM mrdata: there is not much sense to designing custom circuits
07:11 PM mrdata: you can increase range of certain unlicensed things with a reflector
07:12 PM mrdata: or potentially, install a repeater between source/dest
07:22 PM Tom_L: years ago i had a pair of fcc approved transceivers but i can't recall what they were now
07:22 PM Tom_L: from DK
07:22 PM Tom_L: like a 2.5 - 3" antenna
07:23 PM Tom_L: if i knew where they were i'd give em to ya
07:25 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/old_misc_files/old_misc_index.php
07:25 PM Tom_L: haha found a pic of it
07:26 PM Tom_L: https://www.mouser.com/new/linx/linx-humpro-transceiver/
07:26 PM Tom_L: same company
07:27 PM Tom_L: https://linxtechnologies.com/wp/product/nt-series-rf-transceiver-module/
07:27 PM Tom_L: gartt, ^^