So, i have to choose between this 2 tcxo LNB's
Hi,
as already asked, it is important what you intend to receive and what the further receiver chain will look like.
On the one hand, the frequency stability of the LNB depends on the operating mode, and on the other hand, the IF. If a standard RX follows, an IF on 435 MHz may make sense. If strong mobile radio signals are present in the LTE range, an IF around 735 MHz (25 MHz TCXO) can be disturbed.
I see the antenna is 1.8m, so I guess DATV is also an option?
Then an LNB with simultaneous horizontal and vertical output would be good.
Without more precise information, an LNB cannot be recommended.
73 de Robert, DD4YR