SOLVED - RF Link Transmitter/Receiver

For all those who have problems interfacing the RF Link Receiver with a logic-level port:

Connect the data pin of the receiver to an op-amp (I used LM358, just 0,69 ?)
and choose the two resistor to make a non inverting amplifier:

tx of receiver -----> non inverting pin of op-amp (+)
GND -----> R1 -----> inverting pin of op-amp (-) -----> R2 -----> output voltage of op-amp -----> rx pin of serial port

i choose R2 = 4,7 KOhm and R1 = 1KOhm

the output voltage is vo = (1+R2/R1)vs, where vs il the voltage output of the tx pin of the receiver

I hope this will be helpful.

Alex