[DisasterRadio] Fwd: [sudo-discuss] diaster.radio modulation scheme tests

hey adam, this is rad! fyi there's also a disaster.radio mailing list (fwd'ing) ---------- Forwarded message --------- From: Adam &lt;me(a)adammunich.com&gt; Date: Wed, Apr 25, 2018, 21:39 Subject: [sudo-discuss] diaster.radio modulation scheme tests To: Sudo room &lt;sudo-discuss(a)lists.sudoroom.org&gt; Hi all, I ran some tests on LORA modulation schemes to get the best results I could on a 100mW TX power budget. I nearly ran out of gas during this latest test, and unfortunately I managed to screw up my data logging, so I don't have RSSI or SNR data, but this map contains all the places I stopped and got a two way signal on my jet ski. The transmitter was in my hand, the receiver was at pier 50, SF. DIY half wave dipoles were used, with a center freq of 900MHz with a +/- 100MHz 3db roll off. https://www.google.com/maps/d/u/0/edit?mid=1dE2QZS9cgX_oHLWyzmUNAYrjlbX0wJp… I found that quarter wave antennas are no good (see the red markers). The blue markers are today's test, using RFM95's from HopeRF. To get the very long range, I used the following modulation scheme using the RadioHead library. RH_RF95::ModemConfig modem_config = { /*Reg 0x1D: BW=125kHz, Coding=4/8, Header=explicit*/ (7 << 4) | (4 << 1) | (0), /*Reg 0x1E: Spread=4096chips/symbol, CRC=enable*/ (12 << 4) | (1 << 2), /*Reg 0x26: LowDataRate=On, Agc=On*/ (1 << 3) | (1 << 2) }; RF95.setModemRegisters(&modem_config); In other news, you can still jet ski if your core body temp is 88F. Little unpleasant though. - - - - Begin automatically generated footer - - - - I seek to understand, and aim to create. Weblog: http://adammunich.com PGP Public Key: https://pgp.mit.edu/pks/lookup?search=adam+munich _______________________________________________ sudo-discuss mailing list sudo-discuss(a)lists.sudoroom.org https://sudoroom.org/lists/listinfo/sudo-discuss