Satlink meters can be unreliable. Some posters here have had problems with them.
You're correct, the WS-6906 can only decode DVB-S signals, not DVB-S2/MPEG4.
It will still receive DVB-S2/MPEG4 signals (but not measure them accurately) but will not display pictures from those signals.
If you are looking for a good, cheap satellite meter (but without the ability to display pictures) this is the one I'd recommend.
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