[1000mp] CAT control port isolation

[Glenn Valenta (K0BO)]

John Becker wrote:
> I'm setting up my FT-1000MP Mk. V with a Navigator interface. I've read 
> that some users have found the RS-232 chip in the FT-1000 to be somewhat 
> prone to failure, so I thought I'd look into an optical isolator for 
> protection.
> 
> VA3CR's site at http://www.va3cr.net/Interfaces/Optocat.htm has the 
> design such an isolator, but I don't have many of the parts and I wanted 
> to get this setup operational ASAP, so I looked for a manufactured 
> alternative. I ended up buying a Serialcomm - Model ISO-232-3P9.
> http://www.rs232-converters.com/converter_specs/ISO-232-3P9.pdf
> 
> The radio communicates properly with the Navigator without using the 
> isolator, but with the isolator installed there is no communication 
> between the two units. Either the isolator is defective, or it's not 
> appropriate for this application. Any suggestions? Thanks!
> 
> 73,
> 
> John, K9MM

A side note that may help

If the computer and radio are within a few feet, a good ground between them 
will make it near impossible to take out any chips on the radio or the puter. I 
have seen may hams who have several feet between the radio and other equipment 
where not just static, but high RF commonly takes out components. As I often 
work in high RF environments that includes allot of lightning, a good ground 
system has prevented any damage in my 30 year career and my shorter ham hobby. 
Of the damage I had, they were direct strikes that did fairly minimal damage.

If I may suggest that keeping cables very short also helps. I make each cable 
to just 16" more then the direct path between the gear. I also put ferrite 
chokes on all of them. No coils as I think they inductively pick up garbage.

If your shack is large,  you will probably want the optoisolator
Hope this helps!

73  K0BO   Glenn