Search found 49 matches

by AH6DL
Sun Sep 20, 2015 8:00 am
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux - Working!!

After much testing using the debug code in my previous post, I think I now have a version of the gr-osmosdr library sdrplay_source_c_cc that will work as well as it can without major code modification such as using a FIFO buffer to allow fixed output packet size. I'm not seeing any dropped packets, ...
by AH6DL
Sun Sep 13, 2015 1:27 am
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux

I modified my gnuradio-companion test program to show AM demodulated base-band output, both as a scope display and an FFT frequency display. This made it a bit easier to track problems. The modified code is available here: http://www.transmitter.com/sdrplay/sdrplay-airspy-gr-osmosdr-test-2.grc.txt H...
by AH6DL
Fri Sep 11, 2015 3:24 pm
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux

@Amish - Thanks for testing it. Last night i configured my B200 as a 440 MHz signal generator and did some more testing of the original and modified code. As I suspected, even the latest code is dropping or corrupting packets, just different ones. Comparing the baseband output from my Airspy and the...
by AH6DL
Thu Sep 10, 2015 7:12 am
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux

Another day, another problem. Additional testing with the code in the previous email showed that packets were being dropped. This resulted in T8 CW reception, no noticeable problems with SSB and AM reception, but patterned noise in a NOAA 15 APT recording made on a pass this afternoon. The lost pack...
by AH6DL
Wed Sep 09, 2015 6:57 am
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux

I've got the sdrplay_source_c.cc code working quite a bit better. SSB reception works well and the output is generally stable. To ensure the buffer size wasn't an issue, I upped it to 2064 for this version. Lower values may work fine. The latest revision is at http://www.transmitter.com/sdrplay/sdrp...
by AH6DL
Tue Sep 08, 2015 6:58 am
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux

When you keep running into dead-ends, sometimes it's best to go back to the beginning and start over. Taking a different approach to putting a band-aid on the SDRplay gr-osmosdr code -- I say band-aid because this is not a complete solution, I decided to go back to the original code and add an "if" ...
by AH6DL
Mon Sep 07, 2015 5:10 pm
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux

I tried changing the 0904-22 code and modifying the comparison in the "while" loop. I was able to reduce the remaining "cnt" close to zero but this resulted in lower frequency, but more disruptive, errors. I also tried different divisors when storing the buffers and there was either no improvement o...
by AH6DL
Mon Sep 07, 2015 12:45 am
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux

After playing around a bit, I think the test-0904-22 of sdrplay_source_c.cc is the most stable. See the previous posting for details. The major problem with it is the cyclic amplitude and frequency shift. It is occurring at a regular rate so it should be possible to eliminate it. You can see the imp...
by AH6DL
Sun Sep 06, 2015 6:54 pm
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux

I added some debug code to sdrplay_source_c.cc to see how the packets were being handled. Here are the changes to the unmodified (current) sdrplay_source_c.cc: Download: http://www.transmitter.com/sdrplay/sdrplay_source_c.cc.orig-debug.txt The modified sdrplay_source_cc::work : int sdrplay_source_c:...
by AH6DL
Fri Sep 04, 2015 7:10 am
Forum: Code Corner
Topic: Linux
Replies: 54
Views: 91910

Re: Linux

Fixing the gr-osmosdr SDRplay library is going to take some work, and I came up with a tool that should be useful in seeing if code changes actually fix anything. Download GRC file: http://www.transmitter.com/sdrplay/sdrplay-airspy-gr-osmosdr-test.grc.txt http://www.transmitter.com/sdrplay/sdrplay-a...