do two sept. instances of weewx using weewx-sdr require to rtl-sdr radios?

[William Garber]

Suppose you have two weather stations each represented by a respective different simultaneously running instance of weewx.  Both instances of weewx use weewx-sdr as driver for a rtl-sdr radio device connected by usb to the computer.  You have to configure the rtl-sdr radio using rtl_433 which in turn uses the rtl-sdr linux driver. 

The question may be really dumb but don't you have to have two separate rtl-sdr radio devices (each on different usb connections) to run both weather stations at the same time?

[William Garber]

how about if you run two instances of rtl_433 and one dongle using rtl_tcp sending to both rtl_433s.

[storm...@gmail.com]

I would assume that you would need to separate SDR dongles, since the rtl_433 instance #1 would claim the usb port for the SDR Dongle.  What are the frequencies for both the weather stations?  If the frequencies are the same; i.e. 433MHz or 915MHz, you should be able to decode both stations with one dongle.  Or if they are different; i.e. 433MHz and 915MHz and don't mind the possibility of missing packets, you should be able to decode both stations with one dongle by hopping between both frequencies. 

[William Garber]

In the past I had sensors with different frequencies and did frequency hopping.  It was a little slow but worked.  Now everything is the same frequency (I got rid of the sensors on dift. frequencies).  I think the idea of rtl_tcp http://manpages.ubuntu.com/manpages/trusty/man1/rtl_tcp.1.html  is that it allows data from one single specific SDR dongle to be read by multiple radio programs, for example rtl_433 which does accept input from tcp I think looking at the "-d" option in the manpage.  Or I could just shell out $25 bucks and get another dongle.  The overall idea I am examining is

(1) arduinos with sensors and  RFM96W radios transmit using radiohead "RH ASK" to the rtl-sdr.

(2) the rtl_tcp service on my computer sends it to one rtl_433 for each respective weather station.

(3) "RH ASK" device driver (number 67) in rtl_433 gets data.

(2) modify rtl_433 driver (number 67) to accept my data

(3) rtl_433 output can then be used as input to the weewx-sdr driver

(4) weewx-sdr driver would have to be modified also

each weather station has its own instance of weewx which has a separate (instance of the) weewx-sdr driver which has its own (instance of the) rtl_433 driver.

In this setup each weewx instance can access all the data.

[William Garber]

you can see rtl_tcp would be somewhat of a bottleneck on the rtl-sdr dongle but at least it is not a bottleneck on an arduino.