Noob with a question

[ryanroks]

Hey everyone!

Beginner here, going to attempt to build a Portsdown transmitter to transmit random videos to my TV - just for fun. I do, however, live in the US and would rather use ATSC or QAM, instead of DVB-S. Televisions here dont have a DVB-S receiver built in, and having to buy an extra STB makes the project less fun for me

My question is - what components do I need to change in order to modulate QAM frequencies instead of DVB-S? Is it just software (hopefully ) or are there hardware changes involved as well?

My research has only turned up 1 result so far: https://github.com/F5OEO/rpidatv/issues/9

[G8GKQ]

Hi Ryan

Sorry to disappoint you, but neither the Portsdown software or hardware is capable of producing ATSC or QAM. The filter-modulator board is QPSK only, and I doubt that the RPi is powerful enough to drive to drive an SDR with the signals it needs for ATSC or QAM.

You would need to use a more powerful PC with an SDR, such as the Lime SDR or ADALM Pluto, to generate QAM. I am not aware of any software for generating ATSC, but someone might have published something to work with GNU Radio.

Dave

[G4GUO]

The majority of Digital Amateur TV in the U.S uses DVB-T using Hides equipment.

- Charles