Cable God needed.

[lowtech1]

Is it possible to make a homemade RS232 (9 pin) serial cable that is longer than 50f. I?m looking at making a 100~150f cable to connect to an imbedded device at 1200 bits/sec

 

[Harvey]

You could build or buy an RS232 buffer. All you need to build it is a bi-directional buffer chip and a 5 volt supply. The most expensive part will probably be the box you mount it in.

 

[Praetor]

What Harvey said.

 

[bandXtrb]

What's the imbedded device that is 150 ft away?

 

[d33pt]

maybe try using cat5 to make the run.. cat5 is rated at 100mbit for 300ft, so it certainly can handle 150bytes/s. i do realize that data transmission is totally different, but it's worth a try

 

[etech]

As Harvey said they make buffers to extend the length of RS-232 runs.

If this isn't mission critical you can also buy low capacitence RS-232 cable. I've made runs of about 300' at 9200 with it.
Example only, I bought from Belden but don't have my catalog with me right now.
extended distance cable
blackbox

You can also search the Blackbox site for examples of RS-232 line drivers. There are a number of different types. I've used a type that converts the signal to 485 for the distance and then back to 232. You of course need two of them.

 

[lowtech1]

It is for an ozone injection & water filtration controller.