Originally Posted by Ron Marcus
Those are the 2 modules that www.rentron.com sells and I've been using them for a few years now. I've used them successfully and continuously at 9600 baud for quite awhile.
If I would have to quantify the reliability at various baud rates off the top of my head, I think this is what I'd get:
300 baud - almost 0% - too slow, the data slicer loses it's mind since each bit is over 3ms long, each byte 33ms. Even with manchester encoding.
1200 baud - > 90% - if the data coming in is manchester encoding and is continuous, the data slicer doesn't lose it's mind. If there is any pauses between characters, the number goes down.
2400 baud - better than 1200, but you can tolerate a bit longer pause between characters, and again, must be manchester encoded.
4800 baud - > 90% - same reasons as 2400, but now the transmitter is getting bit harder to turn on/off reliably.
9600 baud - about 75% - getting a bit too fast for the receiver now. Although I had one project that would only run at 9600 baud for some reason and had good range, > 200ft. And I found that if you sync the RX with a bunch of $55 first, you could send raw data (not manchester encoded) for quite awhile before the data slicer in the RX forgot where it was.
19200 baud - same as 9600 with reduced range.
Anything higher than 19200 baud would fail almost completely.
If you're still having problems, look at this recent thread I had with lerameur ( http://www.picbasic.co.uk/forum/showthread.php?t=5144 ). We went from start to finish and got it working. The key is manchester encoding when working with these modules.
JDG
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