Working Narrowband FM examples?

Hello,

I am seeking a working NBFM receiver example, as the one on the wiki[0] produces unintelligible output. I am confident that my hardware is functioning properly because if I tune to the same frequency (162.525 MHz ) in gqrx, I can hear the weather radio broadcasts clearly. I am on OpenSUSE Tumbleweed, running gnuradio 3.8.x with a HackRF One and a standard telescopic antenna.

I have reproduced [0] verbatim except with the following change: Instead of a ZeroMQ source, I am using an osmocom source for my hackrf.

I've also tried adapting the flowgraph from the "SDR with HackRF" tutorial[1], which implements a wideband FM receiver in gnuradio, but I wasn't able to make it produce anything resembling speech when I changed it to narrowband FM.

Additionally, I've tried a few NOAA weather radio flowgraphs found online but most of what I've found either didn't work or else was for an older version of gnuradio and thus had errors that I wasn't able to work around since I am a gnuradio novice.

Can anyone recommend a working flowgraph for narrowband FM, ideally something simple and working in gnuradio 3.8+?

Thanks,

Nathan

[0] https://wiki.gnuradio.org/index.php/Simulation_example:_Narrowband_FM_transceiver#NBFM_receiver
[1] https://greatscottgadgets.com/sdr/1/