RV901H/921H/931H is upgraded from the 8th generation system RV801. Compared with RV801, RV901 has all functions of RV801 and can replace RV801, besides, RV901 is added the following functionality. Once the receiving card has been mounted, plug the IDC breakout board in to the receiver card. Make sure that it’s plugged in oriented as shown above.
Please read the originial post here: https://www.ledscreenparts.com/product/linsn-rv901t-receiver-card/