yes, all of what you've written appears to be correct.  The "-L" option should log to disk a series of WAV files containing decoded audio, the contents of which should be controlled by any whitelisting/blacklisting that you've set up.  Suggest you get the basic receiver working first in "interactive" mode before adding the logging option.  I don't recall that there are any interactions with -L with other options (aside from the blacklists/whitelists, if you have any)...  Don't think you'll need any command line audio options though, such as -O or -U... Looks like you're not using the Osmocom build of OP25 - not sure how well -L has been tested in that version... Max On Monday, July 22, 2019, 6:13:52 PM EDT, scancaster(a)scancaster.net <scancaster(a)scancaster.net> wrote: Before I go down a hole and end in a dead end.... I have some questions on using the -L option for "logging." Logging in my universe means logging the audio to Dictaphone/tape/disk/CD/what ever physical media... NOT the -v option, thats a log, not logging! :) ;) So after reading about 30 different files on this -L option, it appers that it will act as A LOGGING RECORDER and RECORD the audio to disk... Great! What I am after is to record UNKNOWN GROUPS for analysis for ID purposes.... My question(s) are what options are used with this for: rx.py trunk.tsv whitelist.tsv blacklist.tsv ie: rx.py example ./rx.py --args 'rtl' -N 'LNA:47' -S 2400000 -f 8xx.xxxxe6 -o 25000 -q 72 -L 4 -v 10 -T trunk.tsv -V -2  -U -O loop0 -M mysystem.json -l http:192.168.0.26:8080 -x 3 2>> stderr.2 trunk.tsv then REQUIRES a "center frequency" for the system... 8xx.xxxx based on the channels of the system... I've determined this for this system,  and it will just fit the way this is setup. This will then RECORD the various groups that are NOT BLACKLISTED to disk as WAV's from what I understand... Correct???? Ie: OP25 tunes to a group, it records it. Anything that is exlusive of each other on this -L option with other optons for rx.py???? Any thing I am missing in this????? Goal is simple to log any group I've not blacklisted as known user/use.. Thanks.