hackrf_transfer replay failure

[mossmann]

Waveforms captured with hackrf_transfer (RX) don't seem to be reproduced properly when replayed by hackrf_transfer (TX). See http://nine.pairlist.net/pipermail/hackrf-dev/2013-July/000110.html

[mossmann]

I'm pretty sure there is no actual bug here, but I'm leaving it open just in case anyone else wants to comment.

[gsj0791]

this is very important, when i test my hackrf one transmitter i can't find any signal at RTL-SDR.

[NeuerUser]

Seem to have a similar problem.

Recording is done via:
hackrf_transfer -s 2 -f 432000000 -r test

test samples are transmitted via third party transmitter on 433.525 and 433.625 MHz

Replay is done with:
hackrf_transfer -s 2 -f 432000000 -t test

some transmitted samples can be found at app 431.965 MHz.

[mossmann]

NeuerUser: two samples per second (-s 2) is not supported. The minimum supported sample rate is 2000000. Additionally, you would probably need to increase the gain settings for rx and/or tx.

[mossmann]

I've had multiple reports from people in recent months who have done successful replay with hackrf_transfer.

[NeuerUser]

Hi Michael

Thanks. Maybe a small example for hackrf_transfer is needed. I followed exactly the following procedure on youtube: https://www.youtube.com/watch?v=vHHRGOxcc-0
The command line (with -s 2) seems to work there (strange).

[NeuerUser]

OK, played around with the options a bit and I got it working with:
hackrf_transfer -s 2000000 -f 432000000 -r test
hackrf_transfer -s 2000000 -f 432000000 -t test -a 1 -x 24

(I am still wondering why it worked for alaindecarolis in the youtube video. Has the syntax maybe been changed in hackrf_transfer at one time? Which version of the hackrf_tools should we use anyway with the KS hackrf one? I am currently using git-31c82a87.)

[gusevargas]

Hi, I have observed similar behavior. I'm running Ubuntu 18.04 and I have an RTL-SDR and the HackrF One both in separate USB ports. Using gnuRadio-companion to receive the signal, and the Hackrf_One to transmit the signal (file) either an .s8 or .f32 format.
In either case, as soon as I execute the command, I get the hackrf_open() failed: Resource busy (-1000)