Remote Rig

RRC 1258 Support in English => General discussion forum => Topic started by: G3UEG on 2010-10-18, 21:30:57

Title: RS232 port isolator help
Post by: G3UEG on 2010-10-18, 21:30:57
In another thread I said I was going to try an RS232 port isolator to try to cure my RFI problems with TS-480 and SPE amp.

After a week of searching and discussions with suppliers I have been unable to find anything suitable.  I need to isolate TXD, RXD and also the DTR line (pin4) which is used for turning the amp on/off with a 200m/s pulse.

Many products only isolate TXD/RXD.  Many products derive their power from the RS232 port itself, which is not available from the RRC or the SPE amp.  I have found a product that has provision for an external power supply, but it only isolates the RTS/CTS in addition to the TXD/RXD.  Another product allows any 2 additional handshaking lines to be isolated (selection by jumpering) but it has to be self powered.

1) Does anyone have details of a product that meets the specification?

2) This might be a stupid suggestion but would it be possible to take the DTR line from the RRC and route it through either the RTS or CTS circuit of an isolator and then route it back to the DTR line on the SPE amp?

3) Might it be possible to design and build ones own isolator - any ideas?

Dave, G3UEG
Title: Re: RS232 port isolator help
Post by: OK1AU on 2010-10-18, 23:08:56
Hi Dave see here:

73 Stan OK1AU
Title: Re: RS232 port isolator help
Post by: G3UEG on 2010-10-19, 12:25:26
Hi Stan,

Thanks for the link.  It looks like just what I need. I will drop them an email.

Dave, G3UEG
Title: Re: RS232 port isolator help
Post by: sm2o on 2010-10-19, 18:25:20

you have to cross the wires anyway so he only important thing is that you have 2 connections in one direction and at least one in the other, What they are named can't be important

73  de mike