Bought a second hand Triax110 dish with three LNB's for 20 Euro's total. Two LNB's were Inverto 'Red Extend' (never heard of this type). After opening it, it seemed that they contain a 25 MHz crystal, so a good candidate to submit to a novel external REF injection method.
Now both xtal pins are fed with the REF signal with opposite phase.
A friend of mine says this improves phase noise of the PLL.