▁trans ponder ▁▁ 2 4 0 0 . 0 5 0 ▁- ▁▁ 2 4 0 0 . 3 0 0   M Hz ▁U pl ink ▁▁ 1 0 4 8 9 . 5 5 0 ▁- ▁ 1 0 4 8 9 . 8 0 0   M Hz ▁Down link ▁ ▁W ide band ▁digital ▁trans ponder ▁▁ 2 4 0 1 . 5 0 0 ▁- ▁▁ 2 4 0 9 . 5 0 0   M Hz ▁U pl ink ▁▁ 1 0 4 9 1 . 0 0 0 ▁- ▁ 1 0 4 9 9 . 0 0 0   M Hz ▁Down link ▁ ▁Hard ware ▁ ▁The ▁first ▁amateur ▁sat ell ites ▁contained ▁te lem etry ▁be a cons . ▁ ▁Since ▁ 1 9 6 5 , ▁most ▁OS C AR s ▁carry ▁a ▁linear ▁trans ponder ▁for ▁two - way ▁communic ations ▁in ▁real ▁time . ▁ ▁Some ▁sat ell ites ▁have ▁a ▁bullet in ▁board ▁for ▁store - and - forward ▁digital ▁communic ations , ▁or ▁a ▁dig ipe ater ▁for ▁direct ▁packet ▁radio ▁connections . ▁ ▁Or bits ▁ ▁Am ateur ▁sat ell ites ▁have ▁been ▁launched ▁into ▁low ▁Earth ▁or bits ▁and ▁into ▁highly ▁elli pt ical ▁or bits . ▁ ▁Oper ations ▁ ▁Sat ellite ▁communic ations ▁ ▁Currently , ▁amateur ▁sat ell ites ▁support ▁many ▁different ▁types ▁of ▁operation , ▁including ▁FM ▁voice ▁and ▁S SB ▁voice , ▁as ▁well ▁as ▁digital ▁communic ations ▁of ▁A X