BATC Forum

I played around with my knucker, DATV Express card and the DATV Express software provided by Charles G4GUO (LP17)
I can receive my own transmission from 500K to 8M bandwith ! (given the good parameters are used) but never
achieved an audio/video reception on a commercial set top box at home or on an SR system (at 1Mhz BW).
In both cases the screens turns black showing "something is coming" without complaints/error messages but
no audio heard, no video shown...(yes I was in 1M BW, mpeg2 audio/video, with a resolution of 768x516 for test with SR system,
and 8M BW H264 for test with my set top box), and knucker was happy with those configurations.
So wrong parameters on my side or known incompatibility with the stream provided by the software ?
73 - Christian

I can't quite work out what you are trying to do, nor why anyone would want to still use SD MPEG2 8MHz in 2021. Are you saying the Express can't drive higher bandwidth to commercial set top boxes?

The Knucker is aimed at low bandwidth DATV and Express was modified to support it and works with the associated DVB-T transmissions as you have verified. As I recall, LP17 was at special edition of Charles' software intended for low bandwidth. As such it might not work so well above 1 MHz. Try one of the older versions perhaps? https://www.datv-express.com/CustomPage/Downloads

Mike

hi Mike,
to clarify

"why anyone would want to still use SD MPEG2 8MHz in 2021"
One test was for me to send 8M BW DVB-T (well received by knucker) and to check
if a "standard" TV set (here it was a commercial set top box with SCART connector output)
was receiving it..Answer is no, it didn't work. Why ? I don't know, so my question !
Why did I made this test : for fun, only to experiment, nothing else.

The other test was made with my ATV neighbor F3YX
He transmitted 1M DVB-T Mpeg2 from his SR-systems, and it was received by me on knucker.
So I transmitted to him the same format "1M DVB-T Mpeg2" because his system only
allows this codec, but he never got an image displayed or heard a sound despite a
good reception on his side (SSI & SQI =100%)
So my question...

No Mike, I don't live in the past, I was on QO-100 WB the first day

BR

Whoever said you lived in the past? Anyway that clarifies it. It is probably something to do with the metadata for the transport stream and the box not understanding what to display. I don't know what the commercial boxes are expecting but perhaps you can get a clue from the SR systems TS you received?

Quite a few years ago, ~2016, I sent DVB-T from my PC to my TV using Gnuradio. Mostly to the example DVBTX. Perhaps have a look at that and see what it sets.

Mike