Greetings group members

Given the huge price of the Lime SDR, I was trying to find alternative methods for setting up an AMPS test rig.

I found this command that operated half of the time rx and half tx, but it was of no use.

At one point I saw "Signal received" on the console but it did not show further signs of life.

My questions are, please:

- Is there any future with this approach? - if nor, woukd be possible to use the hackrf to transmit, and a RTL-SDR to receive?

Thank you very much

test@test-ThinkPad-T470:~$ SOAPY_SDR_LOG_LEVEL=DEBUG sudo amps -v 1 -k 313 -F yes --sdr-soapy --sdr-device-args "driver=hackrf" --sdr-samplerate 5000000 -s 200000 --sdr-tx-gain 15 --sdr-rx-gain 0 -S sid=1 --sdr-timestamps 0 --sdr-lo-offset 0

And the output;

DOPTIONS INFO options.c:128 Config file '/root/.osmocom/analog/amps.conf' seems not to exist, using command line options only. DOPTIONS INFO options.c:280 Command line option '-v' ('--verbose'), parameter '1' DOPTIONS INFO options.c:280 Command line option '-k' ('--kanal'), parameter '313' DOPTIONS INFO options.c:280 Command line option '-F' ('--flip-polarity'), parameter 'yes' DOPTIONS INFO options.c:296 Command line option '--sdr-soapy' DOPTIONS INFO options.c:294 Command line option '--sdr-device-args', parameter 'driver=hackrf' DOPTIONS INFO options.c:294 Command line option '--sdr-samplerate', parameter '5000000' DOPTIONS INFO options.c:280 Command line option '-s' ('--samplerate'), parameter '200000' DOPTIONS INFO options.c:294 Command line option '--sdr-tx-gain', parameter '15' DOPTIONS INFO options.c:294 Command line option '--sdr-rx-gain', parameter '0' DOPTIONS INFO options.c:280 Command line option '-S' ('--sysinfo'), parameter 'sid=1' DOPTIONS INFO options.c:294 Command line option '--sdr-timestamps', parameter '0' DOPTIONS INFO options.c:294 Command line option '--sdr-lo-offset', parameter '0' Selected System ID (SID) 1 belongs to: Chicago, IL (Cellular One) DDSP DEBUG dsp.c:150 Generating sine table for SAT signal. DAMPS NOTICE amps.c:583 You selected 'combined control & paging & voice channel'. This is a hack, but the only way to use control channel and voice channel on one transceiver. Some phones may reject this, but all my phones don't. DAMPS DEBUG amps.c:597 Creating 'AMPS' instance for channel = 313 of band A (sample rate 200000). DSENDER DEBUG sender.c:77 (chan 313) Creating 'Sender' instance DJITTER INFO jitter.c:129 (313) Reset jitter buffer. DJITTER INFO jitter.c:113 (313) Created jitter buffer. (samperate=8000, target_window=60ms, max_window=1000ms, flag:latency=true flag:repeat=true) DJITTER INFO jitter.c:129 (313) Reset jitter buffer. DJITTER INFO jitter.c:113 (313) Created jitter buffer. (samperate=200000, target_window=60ms, max_window=1000ms, flag:latency=true flag:repeat=true) DDSP DEBUG dsp.c:202 (chan 313) Init DSP for transceiver. DSENDER DEBUG sender.c:308 (chan 313) Maximum deviation: 8.0 kHz, Maximum modulation: 10.0 kHz DSENDER DEBUG sender.c:309 (chan 313) Deviation at speech level: 2.9 kHz DDSP DEBUG dsp.c:218 Use 20.0000 samples for full bit duration @ 200000. DDSP DEBUG dsp.c:234 Bit window length: 20 DDSP DEBUG dsp.c:235 -> Samples in window to analyse level left of edge: 5..9 DDSP DEBUG dsp.c:236 -> Samples in window to analyse level right of edge: 10..14 DDSP DEBUG dsp.c:175 Generating smooth ramp table. DDSP DEBUG dsp.c:259 Sat detection interval is 66 ms. DDSP DEBUG dsp.c:927 (chan 313) SAT detector reset: Initial state. DAMPS DEBUG amps.c:399 (chan 313) State change: (NULL) -> IDLE DAMPS INFO amps.c:685 (chan 313) Entering IDLE state, sending Overhead/Filler frames on combined control & paging & voice channel. DDSP DEBUG dsp.c:927 (chan 313) SAT detector reset: Change to FOCC. DDSP INFO dsp.c:944 (chan 313) Change mode to FOCC DDSP DEBUG dsp.c:967 (chan 313) Reset FSK frame transmitter, due to setting DSP mode. DAMPS NOTICE amps.c:638 Created channel #313 (System A) of type 'CC/PC/VC' = combined control & paging & voice channel Base station on channel 313 ready (combined control & paging & voice channel), please tune transmitter to 879.390 MHz and receiver to 834.390 MHz. (-45.000 MHz offset) DLCC DEBUG endpoint.c:1376 Creating new endpoint instance. DLCC DEBUG endpoint.c:1209 setting automatic remote peer selection DSDR DEBUG sdr.c:149 Open SDR device DSDR INFO sdr.c:168 Require bandwidth of each channel is 2 * (8.0 deviation + 10.0 modulation) = 36.0 KHz DSDR INFO sdr.c:307 We shift center frequency 18 KHz down (half bandwidth), to prevent channel from overlapping with DC level. DSDR INFO sdr.c:133 TX Spectrum: 1 ---------------------------------------+--------------------------------------- DSDR INFO sdr.c:135 Frequency 1 = 879.3900 MHz DSDR INFO sdr.c:357 Total bandwidth (two sidebands) for all TX Frequencies: 108000 Hz DSDR INFO sdr.c:365 Using center frequency: TX 879.354000 MHz DSDR DEBUG sdr.c:370 Frequency #0: TX offset: 0.036000 MHz DSDR INFO sdr.c:391 Using gain: TX 15.0 dB DSDR INFO sdr.c:433 We shift center frequency 18 KHz down (half bandwidth), to prevent channel from overlapping with DC level. DSDR INFO sdr.c:133 RX Spectrum: 1 ---------------------------------------+--------------------------------------- DSDR INFO sdr.c:135 Frequency 1 = 834.3900 MHz DSDR INFO sdr.c:469 Total bandwidth (two sidebands) for all RX Frequencies: 108000 Hz DSDR INFO sdr.c:477 Using center frequency: RX 834.354000 MHz DSDR DEBUG sdr.c:482 Frequency #0: RX offset: 0.036000 MHz DSDR INFO sdr.c:492 Using gain: RX 0.0 dB DSDR INFO sdr.c:525 Using local oscillator offset: 0 Hz DSOAPY INFO soapy.c:109 Using device args "driver=hackrf" DSOAPY DEBUG soapy.c:83 SDR device args: key='driver' value='hackrf' DSOAPY INFO soapy.c:113 Using stream args "" DSOAPY INFO soapy.c:117 Using tune args "" [INFO] Opening HackRF One #0 16bc62dc2e8526a7... DSOAPY DEBUG soapy.c:176 We have 1 RX channel, selecting channel #0 DSOAPY DEBUG soapy.c:305 We have 1 TX channel, selecting channel #0