[GreenKeys] Problem with Current Loop to RS-232 Converter on ASR33

[Rob Jarratt]

The ASR33 I got came with a little box that I assume to be a Current Loop to
RS232 converter.

The ASR33 behaves rather oddly when I plug the RS232 connector into
anything. When the connector is not plugged into anything the ASR33 ticks
over as I believe it should. However when I plug the connector into a
socket, even if the socket is not connected to anything else, the ASR33
starts acting a little as if it receiving characters, the cylinder with the
characters embossed on it "vibrates" but does not print anything. If I plug
it into my breakout box, with the other end not connected to anything, it
acts in this way and I notice the Rx light come on, which of course it
shouldn't as nothing is being sent to it. It is almost as if there is a
short to the Rx line. I have checked the connector for shorts but there
don't seem to be any.

Has anyone ever come across behaviour like this?

Regards

Rob
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/greenkeys/attachments/20130119/cc9b638b/attachment.html>