Sunday, 24 September 2017

LimeSDR running DATV Express DVB-S TX software

LimeSDR running DATV Express DVB-S TX software (1st draft)

With the MiniTioune DVB-S RX, I have begun trying different TX using DATV Express software under Windows 10. The logical first hardware would be the DATV Express hardware TX, but having shifted rooms in the house, I have not been able to find; I know exactly where it was in the other room!

The LimeSDR is a popular recent SDR dual duplex transceiver by Lime Microsystems using a new version of their own chip. Cost is about US$250, but they have just announced a mini version for about US$150. It replaces the popular BladeRF; I sold mine to by the new model.



DATV Express TX software is available for the LimeSDR; https://discourse.myriadrf.org/t/windows-based-dvb-s-s2-t-transmitter-for-limesdr/1348 (https://wiki.myriadrf.org/LimeSDR-USB) . It worked well without any hitches on 23 cm, with both TX and RX running on the same computer. I am currently using my main PC, but will move it to my fast Dell laptop for project work. With all the test gear, its a real kitchen table job. I might try the table in my new room, just need to tidy it!

One of the purposes of running  DVB-S is to compare power measurement techniques with it and with DVB-T. I have discussed power measurement of wide TV signals in earlier posts.

Another purpose is to investigate cavity notch filters with DVB-S as it seems to have problems with "spread" when the power amplifier is driven too hard. I have done some work with cavity filters and DVB-T, see earlier posts.

More photos when I get it running on my laptop.


Decontis dtvtools DVB-T/S measurement, analysis and monitoring software


Decontis dtvtools DVB-T/S measurement, analysis and monitoring software (draft) 

Introduction

There has been a lack of good DVB-T monitoring software for both TX monitoring and RX measurement, unlike DVB-S that has Tutioune. I came across a commercial grade package from decontis that is relative inexpensive and uses a cheap USB-T dongle. While comprehensive, it is not particularly easy to use, but is network-based. I have managed to get it going and plan to use it for TX power amplifier modification and monitoring. My favorite element is a proper constellation chart.

Other software and hardware

The available DVB-T measurement, analysis and monitoring software is limited. CrazyScan2 for terrestrial/cable DVB-tuners https://sourceforge.net/p/crazyscan/wiki/Info/ uses PCTV USB tuner. The other alternative is to use a TV tuner, which gives MER and BER, but not constellation diagrams. A standalone TV installer instrument can be used, but good ones are expensive. Professional equipment is very expensive.

For DVB-S there is the excellent Tutioune; http://www.vivadatv.org/page.php?p=tutioune-en

Decontis

Decontis dtvtools is an excellent DVB analysis and monitoring software package. It is available for DVB-T, DVB-S and others. It is complex, commercial grade software but relatively inexpensive. http://www.decontis.com/

The DVB-T bundle, comprising SAMalyzer, SAMcorder, SAMitor, SAMbuddy-RF, SAManalog, SAMager-Agent, and SAMrack, is shareware and 50 € to buy. It is amazing value.

There is virtually nothing on the web on how to use it. A non-English YouTube is helpful. https://www.youtube.com/watch?v=T08c2yv8MeI

There are manuals for each module but none are particularly useful for setting the package up for first time use.

The sequence to use it is to install everything and connect a supported TV tuner. Start SAMcorder, use default settings and read the manual, scan your local TV stations and select one frequency. Use IP stream as output. Starting services will bring up another SAM window, select one frequency/stream, open to show channels. Clicking a channel will bring up SAMitor and the TV picture. Start SAMbuddy-RF and open both links to start analysis. Click constellation and start it to give constellation diagram. Then sit back in awe if it all works!


Use other components as desired, it helps to read the manual as it is complex software.

Issues

The software is limited by the tuner in terms of bandwidth. My interest is high quality DATV on 70cm and can use 7 MHz. I use a PCTV TripleStick 292e USB that can do 6, 7, and 8 MHz. Generally, dtvtools only supports tuners which support Microsoft DirectX BDA technology.

It is possible that the HiDes RX dongles might work as they are BDA. I quickly tried an old UT-100D with no success, but I am fairly sure it was the wrong driver. It unsuccessfully scans the device. I will investigate further later.

The software is available as a DVB-S bundle. I haven't tried it. It is hard to beat Tutioune hardware and software.

SAMcorder has an ASI input and a IP stream output which may be of interest to some.

TV Tuner

For compatible tuners see p6 of SAMbuddy-RF. Others may work. Generally, dtvtools only supports tuners which support Microsoft DirectX BDA technology.

I use a PCTV TripleStick 292e USB. It is a pretty amazing device, like most tuners, a SDR frontend.

http://www.pctvsystems.com/Products/ProductsEuropeAsia/Hybridproducts/PCTVtripleStick/tabid/308/language/en-GB/Default.aspx

http://blog.palosaari.fi/2014/04/naked-hardware-15-pctv-triplestick-292e.html

Silicon Labs Si2157 tuner





















MiniTiouner DVB-S receiver build

MiniTiouner DVB-S receiver build (draft)


Works well, some fiddly soldering.

Gives me DVB-S capability

Assembled version coming, about $100 from DATV Express group.

Links

Unique hardware: https://www.batc.org.uk/shop/minitiouner
https://wiki.batc.tv/MiniTiouner_hardware_Version_2
https://wiki.batc.tv/MiniTioune_software
https://www.videohelp.com/software/LAV-Filters
All codecs: https://www.videohelp.com/software/sections/codec-packs
https://wiki.batc.tv/File:Notes_on_building_the_BATC_v2_Minitiouner.pdf