Using SoapyAirspy with RX_TOOLS... how can i activate BIAS-T?

[runahue]

Hello friends: Is anybody using rx_tools (https://github.com/rxseger/rx_tools) with Airspy? Is possible activate bias-t? rx_tools uses SoapyAirspy. A lot of thank's 4 your help.

[guruofquality]

I added support to apply any device arguments to the arbitrary settings when the keys match: https://github.com/pothosware/SoapyAirspy/commit/4a4892eaadea44e3060983088c73d6d8d975eec8

So you can shove "biastee=true" (for example) into the device arguments string which may command line sdr applications support. I didnt test it, so let us know, thanks!

[runahue]

A lot of thank's ! I will test it next days. Now i am fighting with rx_tools.... I think they have some bugs.

[doctorvenables]

bump

I've tried combinations of biastee=true. Stabbing in the dark a bit, Is it -d biastee=true -d biastee=1 -d biastee:1 -d "biastee=true"

or am I missing the right combination completely.

The short term answer is to remove the LNA/filter up by the antenna, try without the biastee setting on the airspy and see if I can get something. Not ideal long term but at least I'd have isolated the problem.

Extra info: I'm on raspbian buster on a Pi4, airspy_rx is completely fine (and I can switch on the biastee with the -b 1 option so I know it works)

[guruofquality]

• The -t option in rx_sdr will write arbitrary key value settings: https://github.com/rxseger/rx_tools/blob/master/src/rtl_sdr.c#L193 The format with the biastee=true would be correct one.

Note that this is only in one of the rx tools applications, if you need it on others please make a pull request to have a command line option with a call to verbose_settings(). It should be a pretty minimal change. I can merge pulls on that repo FWIW

[guruofquality]

This should be an issue with rx tools, closing. thanks!

[doctorvenables]

Thanks for the advice. Appreciate the hard work that's gone into soapyairspy. Have made a pull request (don't know if I've done it right though!)