DVB-T in North America

Want to write your own code to work with a HDHomeRun or work with the HDHomeRun DVR? We are happy to help with concepts, APIs, best practices.
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emveepee
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DVB-T in North America

Post by emveepee »

I ran into a support issue for NextPVR on the forum today https://forums.nextpvr.com/showthread.p ... #pid598698 I have a DVB-T/C/ATSC/QAM modulator and I can feed coax into DVB-T devices so I can test scanning and OTA EPG. My question is can I use a HDFX-4DT in North America or will that screw up things since the channels will not be local, will change often and can be pretty much any country in a setup scan.

If it is possible are these available refurbished, they are relatively expensive for a few tests a year for free software.

Martin

nickk
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Re: DVB-T in North America

Post by nickk »

No problem running a 4DT in NA. You can even run a 4US/4K and a 4DT together - the HDHomeRun app will show all channels across all devices.

If the modulator is replaying things you won't get guide data for the modulated channels.

emveepee
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Re: DVB-T in North America

Post by emveepee »

Great, the Dekltek modulator will send the full mux properly so I expect to that the PID 18 data will be available via rtp and BDA just like we get it today from broadcast via the HDHR. Hopefully I can find a refurb unit sometime.

Note that in this case the userls problem was solved by switching BDA compatibility from Default to NextPVR. I thought default was full mux, can you explain the difference in the filtering?

Martin

jasonl
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Re: DVB-T in North America

Post by jasonl »

Default enables the PID filter, which makes channel tuning an additive process: the application has to request which PIDs it wants. NextPVR mode disables the PID filter, so the full mux is sent. This would a problem for cable users, for example, as US clear QAM (for the few who still have it) is 38.8Mb/s, and DVB-C annex A (European cable) is just over 50Mb/s at the highest symbol rate, and all current HDHomeRun devices have 100Mb/s interfaces. DVB-T and T2 would also run into problems with 4 full muxes going.

emveepee
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Re: DVB-T in North America

Post by emveepee »

That's fine in BDA and RTP modes only the required PIDs are requested. It is only the special case when we need to do full mux for testing scan, OTA EPG etc that we need the full mux.

Martin

jasonl
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Re: DVB-T in North America

Post by jasonl »

You can use IMPEG2PIDMap::MapPID to control the PID filter by adding individual PIDs that are desired for EPG and such, or you can use IHDHomeRun_ProgramFilter::put_ProgramNumber to set the program number (BDA equivalent of hdhomerun_config set /tuner#/program). If you use 0 as the program, it will pass the full stream.

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