according to Satbeams website, The recommended dish size for IS17 is 230cm. What you have is 180cm dish. As @
[U]sskarnold[/U] said, lnb needs better placement, real fine tuning. Fine tune in terms of skew, fine tune for F/D ratio or the placement of LNB in the scalar ring. This is because, in 6ft you get marginal signal and best tuned setup only can get you the real signal with lowest possible noise.
Further, You have to be sure that the dish is not badly handled, is not damaged and reflection from all sides of the dish points to lnb. [If you had ever lifted the dish by its leaf to move, the shape may not remain as intended cut spherical.
Further more, As the Frequency of the Tp is lower and lower, towards 3700MHz, the dish size requirement matters more tightly when our dishes are already smaller from recommended. So you may get the TP 4015V and other 4000+ Mhz but not get 3700, 3800Mhz Tps even if we are are pointing to that satellite. I didn't get lower frequency TPs in my 6ft dish, a week back.