2018-10-27, 11:14 AM
(2018-10-26, 06:24 PM)abarrow Wrote:(2018-10-26, 02:18 PM)PaddyB Wrote:Quote:Uses RTL2832U+R820T2 chip set
100KHz to 1766MHz, operating frequency
Navtex is 518Khz.
Quite correct! These devices tune down to about 50Mhz so my brain erased the Khz and put Mhz in instead
Quick google suggests to tune so low it needs to be in direct sampling mode, the Pi struggles with my fun cube dongle so direct sampling might be pushing it a bit. Anyway, even with a good ham radio getting navtex can be a bit of a chore remembering to turn on at the right time plus the timings of the broadcasts can be a bit out.
One of those dongles might be more use for weatherfax if a good enough signal can be had so low, some stuff on google about the quality not being great tuned so low.
Though a good receiver like a degen 1103 doesn't cost much more than the dongle and will get a much better signal.