hi to all
is there any device or interface can convert dvb t receiver to dvb s receiver?
Yes, but price depends on what you are trying to achieve.
In principle, you can buy a range of DVB-S receiver cards, and then add re-multiplexing software that creates a set of DVB-T streams (nothing free that I'm AFAIK), and a couple of modulators, some adders, and a damping unit, and you should be able to feed this into a DVB-T box.
But this is expensive, and needs configurating etc.
So, do you want to buy lots of (semi-)pro stuff and fiddle with electronics, or were you hoping to "simply" re-use a DVB-S box for DVB-T reception?