focal point setting

[sean2e0saf]

anyone give any pointers on focal point setting prime focus IRTI 1.5m dish i measured the original FP to be about 625mm from the tip of the scalar rings on the original feed horn.. i assume i simply use these same measurements for new lnb and patch antenna waveguide then i put the cap on..?

thanks all

[RimaNTSS]

It is always possible to calculate. You just need to precisely measure diameter and depths of the dish and then enter data in some of the calculators, like this https://www.satellite-calculations.com/ ... lector.htm
Make sure feed is pointed to the center of the dish. Also move feed closer/further and observe when signal lever gets maximum.

[radiogareth]

As above, measure and calculate. I was able to 'prove' by using the sun and putting a small piece of paper to 'see' the focused sun - but my dish is clean alloy - no paint. You can also use your hand......with care if its a big dish - mine is 66 cms and it gets hot!
Gareth