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Navtex
#11
(10-26-2018, 08:41 AM)abarrow Wrote: What about something like this? https://www.aliexpress.com/item/New-Car-...525d09a738

Won't work for navtex or weatherfax unfortunately, doesn't tune low enough. 
Quote:Uses RTL2832U+R820T2 chip set

100KHz to 1766MHz, operating frequency

In node-red I've just had my navtex engine speaking Cool

http://espeak.sourceforge.net/index.html
https://flows.nodered.org/node/node-red-...sysmessage
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#12
(10-26-2018, 07:32 AM)PaddyB Wrote: Hi,   I used node-red, it's not been set up for a while but just found the backup, basically a insert node sends "0x0D 0x0A $S 0x0D 0x0A 0x0D 0x0A" to a serial port connected to the navtex engine for entire memory, then another serial port reads the output and sends it to a file and a node red dashboard. 
Hi
Thanks a lot for the code.  Smile
I will try it next weekend. 
Best regards
Bernhard
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#13
(10-26-2018, 09:18 AM)PaddyB Wrote:
Quote:Uses RTL2832U+R820T2 chip set

100KHz to 1766MHz, operating frequency

Navtex is 518Khz.
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#14
(10-26-2018, 01:24 PM)abarrow Wrote:
(10-26-2018, 09:18 AM)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 Wink

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.
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