DOWNLOAD DATV-Easy v3.08

[radiogareth]

Thanks for the guidance, I'll try that and re-install.
Understood its experimental and as such may do unexpected things. It would be very nice if it can be made to behave as on paper it will out-spec both a Lime Mini and a Pluto.
Gareth

[M0LNG]

Hi Dominique,

I'm one of the HackRF developers if I can be of any help.

I have tried DATV-Easy v3.08 with a HackRF One running the latest firmware and I see the same problems as Gareth: no valid signal generated, and the software does not stop TX when the STOP button is pressed, nor when the program exits.

There is some constant-envelope signal being produced, but it seems to be impossible to lock to. In the Minitioune software a circle appears rather than the expected QPSK constellation. When the STOP button is pressed, the circle disappears and is replaced with noise, but the device stays in TX mode - so I think the program stops sending samples to the HackRF, but does not send the necessary USB request to take it out of TX. If you're using libhackrf directly then I would guess that you are just missing a call to the hackrf_stop_tx function when stopping. If you're using the device via one of the various wrapper libraries then you'd need to find the equivalent operation in its own API.

Note that the issue that you linked above turned out not to be a problem with the HackRF firmware, but rather a bug in the gr-osmosdr package, which provides a cross-device wrapper API and source/sink blocks for use in GNU Radio. Unless you're actually using gr-osmosdr within DATV-Easy, that issue is unrelated except for the similar symptom.

I am pretty sure that the issues here are on the DATV-Easy side, or within whatever libraries are in use, because with the same HackRF unit running the same firmware, I am able to generate valid DVB-S2 signals using GNU Radio.

Happy to help further if I can.

73 Martin M0LNG

[radiogareth]

Hi Martin. Interesting, useful pointers for looking deeper into the issues. I've never used GNURadio but its shortcut sits on my desktop probably from when I first got a Lime SDR.
Is there a repository of flowcharts (bit like SDRAngel has loads of 'plug-ins') to experiment with, particularly DVBS2/T etc. Happy to try stuff out, particularly outside the reach of a Pluto such as below 70MHz.
Gareth

[M0LNG]

Hi Gareth,

There are some example flowgraphs for generating both DVB-S2 and DVB-T that come with GNU Radio, you should have them in an 'examples/dtv' directory somewhere in your install or, they can be readily downloaded. The most relevant ones are called dvbs2_tx.grc and dvbt_tx_2k.grc. These are set up to use some pre-generated TS files that are not included due to size, but can be downloaded from W6RZ's site at:

https://www.w6rz.net/adv16apsk910.ts
https://www.w6rz.net/adv8dvbt23qam64.ts

You can adapt these examples for any TX capable SDR by putting the appropriate sink block at the end of the flowgraph. The HackRF can be used via either the OsmoSDR or Soapy blocks.

[G4NZV]

Hi,
A couple of observations using DATV-Easy V3.08 and HackRF via USB.

1. DVB-S2 333 symbol rate the attached spectrum is observed from the Hack RF. Note the centre of the images either side of the main transmission at 437MHz fall at +/- 666KHz and +/- 1332KHz .... so are presumably related to the Symbol Rate selected of 333KS.

2. If Easy v3.08 is STARTed the waveform attached is shown, however as described in an earlier post the STOP button or EXIT button does not return the HackRF to its non-TX state. To recover the HackRF must be unplugged from the USB port and DATV-Easy execution must be stopped by closing the app. If this is not done it will no longer be able to control or send data or TS to the HackRF.

3. What I found when using GNU radio blocks they will control HackRF correctly using SOAPY commands.

4. Now the very good news I have successfully transmitted and received 333Ksymbols at 437MHz H265 to my RYDE receiver and demodulated the signal with a MER of 18dB (Across the shack so don't pay much attention to the actual MER figure). I have left this running for 20 minutes without any issue.

Hope the above is useful to help continue the development of Easy-DATV as the inclusion of HackRF would be of great benefit to me and others as DATV signals between 1MHz and 6GHz can be easily generated.

Many Thanks for your efforts with this development, happy to test further if that would be helpful.

Steve G4NZV

[radiogareth]

That's good news Steve. Is the waveform you transmitted cleaner than the one from 3.08?
When its sorted it will be a really handy piece of kit/software. How things have changed in 10 years. Amazing progress.
My software capabilities end with BBC basic and uploading Arduino code
Gareth

[G4NZV]

Hi Gareth,

To clarify; the waveform received on my RYDE receiver is the waveform shown in the spectral display generated using OBS feeding DATV-Easy v3.08 then using HackRF to TX. The RYDE receiver was tuned to 437MHz and DATV-easy v3.08 was also tuned to 437MHz.

Steve G4NZV

[g0mjw]

Hi,
A couple of observations using DATV-Easy V3.08 and HackRF via USB.

1. DVB-S2 333 symbol rate the attached spectrum is observed from the Hack RF. Note the centre of the images either side of the main transmission at 437MHz fall at +/- 666KHz and +/- 1332KHz .... so are presumably related to the Symbol Rate selected of 333KS.
efforts with this development, happy to test further if that would be helpful.

Steve G4NZV

What a dreadful spectrum - I think that's from not doing the anti-aliasing or filtering correctly. I hope nobody transmits that on-air.

Mike