HT640 AND ht648L not working

[samuelsathish89]

Hi am transmitting a 8-bit data continuosly. i'm using 433MHz tx and Rx. I tried using Encoder and Decoder. to check them i connected Push buttons and LED in TX and RX side respectively. i didnt find any Led glowing. when checked seperately the 433 Mhz Tx and Rx, its working fine. with encoder and decoder, i'm getting square wave o/p in Dout pin of HT640. but only random noise in RF Receiver Data pin. pls help me out.