I give upp now..... Inverted mode does not work but True mode work just fine whit SERIN, i think it has someting to do whit noise in the air becous when i hold my hand over the antenna of the reciver it works a better but not good.

My solution will be to pull down PDN line when i donīt want to transmitt and pull it high when i want to transmitt or just drive the hole modul from an +5v high PIN on the PIC that is active when i want to transmitt and then pull it low.

Transmitter supply current is 5.2 mA so a pin from the 16F628A that have 20mA is enought.

Then i can use True mode whitout have an RF carrier when i donīt send.