Multiple Program Streams?

Post Reply
N6GKJ
Posts: 19
Joined: Sun Dec 22, 2013 1:35 am

Multiple Program Streams?

Post by N6GKJ » Sun Dec 22, 2013 1:52 am

Hey guys,
Have my DigiLite 5.7 board built up. I have a PVR500 this board has two MPEG2 Encoders separate and complete. There is a plug-in daughter board to input vid/aud to the second encoder. Has there been any discussion of multiple program streams possible with some software mods? I believe the SR Systems TX has this as an add-on option.

Unfortunately, I don't have the required skill set to help with the programming, I am a hardware guy!!

73
Ron, N6GKJ
73,

Ron....
N6GKJ CM98ic

G4EWJ
Posts: 639
Joined: Wed Feb 17, 2010 10:11 am

Re: Multiple Program Streams?

Post by G4EWJ » Sun Dec 22, 2013 2:56 pm

In its earliest development, DigiLite Transmit was written to handle multiple inputs, but that got left by the wayside as development progressed. It may happen one day, but I imagine there wouldn't be much general interest in it.

Brian

N6GKJ
Posts: 19
Joined: Sun Dec 22, 2013 1:35 am

Re: Multiple Program Streams?

Post by N6GKJ » Tue Dec 24, 2013 1:40 am

Hi Brian,

Maybe not in the UK, but here in the States, that is another story. Most of what I am seeing in my reading is there is more usable spectrum on 23cm available in the UK than there is over here, however here in Northern California there are more repeaters in service that NO ONE uses that you can shake a stick at. Unfortunately this ties up spectrum for those who would actually use it. In the 23cm band there are more repeaters here than anywhere I have looked. and NONE of them are busy and most are never used. That coupled with 2 frequencies available for ATV, Not a lot of kiddies share their toy here. If I could put up a Digilite TX with multiple streams, I could get several groups using Mt Diablo with just one TX.

From our perspective, this is a great option!!!

I hope to make my case...if not I can always beg more!!!
73

Ron
73,

Ron....
N6GKJ CM98ic

G4EWJ
Posts: 639
Joined: Wed Feb 17, 2010 10:11 am

Re: Multiple Program Streams?

Post by G4EWJ » Thu Dec 26, 2013 11:46 am

It's always dangerous to say " but why would anyone want to . . . ". :)

It may seem on paper that there's more spectrum on 23cm in the UK, but the 1250-1290MHz section is now marked "keep off the civil aviation radar grass" and so in the north-west of England, there's effectively only the single frequency of 1249MHz available for ATV repeater inputs and simplex contacts.

DigiLite v2 will go up to 9M symbols, so you could run potentially 2 x 4MS or 3 x 3MS on the same transport stream. The limitation is the dsPIC33F. There are plenty of processors that will go faster, but none of a size that I would like to solder. The dsPIC33E series might be an option and could probably be overclocked to give 67% more speed than the dsPIC33F, so maybe 15MS, but some of the functionality has been reduced, so I couldn't be certain without trying it. I can see the attraction of several groups running their receiver into the common transmitter though. It needn't be limited to video and could have several audio channels and high speed data.

Converting DigiLite Transmit to use several inputs is something I'd like to try, but the problem is finding the time to do it.

Brian

M0DTS
Posts: 348
Joined: Sun Feb 24, 2008 9:03 pm

Re: Multiple Program Streams?

Post by M0DTS » Thu Dec 26, 2013 5:51 pm

It can be done roughly with the Opencaster suite in Linux like i did some time ago with two programs in one TS, not a perfect solution though.

Rob

Post Reply

Return to “DigiLite”