Help needed for transmitting 15V signal to 10 metres at 8KB/s using RS232 or RS422 cable

[Prakash123]

The only thing I would question at this point is the choice of ULN2003 Darlington transistor drivers for use as data receivers. Better would be something with hysteresis on the input transition levels, perhaps this quad CMOS receiver.

I would like forum because of getting new idea and I will use DS14C89A in this project.

Your mosfet drivers should provide adequate signal level for reception at the end of ten meters of twisted-pair cable.

I better to concentrate on rectifying problems in existing system.

 

[hevans1944]

I better to concentrate on rectifying problems in existing system.

If by rectifying you mean correcting problems in existing system, that is what we here at Electronics Point have been trying to tell you. But you have not responded with anything useful. In particular, you have not stated whether or not you have an oscilloscope available that you can use to perform signal integrity tests. How can you expect to correct any problems without knowing the exact nature of those problems, which oscilloscope wave forms will surely reveal?

A shotgun approach, where you just throw various parts at the project hoping something will work, is not a good way to design or troubleshoot anything, even if you have deep pockets full of cash and a lot of time to waste exploring the wrong paths.