INTRODUCTION：
STD4 is designed to allow the user to convertan input S.BUS signal into a corresponding PPM signal output.
HOW TO CONVERT BETWEEN 1~4CH AND 5~8CH OUTPUT：
STD4 is designed to convert 1~4channel or 5~8channel signal output from S.BUS signal, when the weldingspot1 and 2 as shown image are welded, the output signal will be 5~8channel, otherwise the output signal is1~4channel.
![[PRE-ORDER] RadioMaster - ER5A-V2 ExpressLRS receiver](http://ueeshop.ly200-cdn.com/u_file/UPAX/UPAX406/2311/02/products/ER5A-1000x1000-9-b177.jpg?x-oss-process=image/quality,q_80/resize,m_lfit,h_500,w_500)
![[PRE-ORDER] RadioMaster - ER5A-V2 ExpressLRS receiver](http://ueeshop.ly200-cdn.com/u_file/UPAX/UPAX406/2311/02/products/ER5A-1000x1000-5-86f2.jpg?x-oss-process=image/quality,q_80/resize,m_lfit,h_500,w_500)