[RFI] router RFI

[Cortland Richmond]

On 3/4/2013 0034, Jim Brown wrote:
> Dale and Cortland -- something you could do for us is provide a good 
> description of the spectra that typically results from Ethernet 
> traffic so

Unfortunately, being retired I no longer have access to test results 
that would refresh my memory, and I (perhaps fortunately) don't have 
Ethernet at home that I could use to rediscover it.  Maybe I'll buy a 
cheap second-hand router and look; I've a "new" Advantest R3621 analyzer 
coming that will need testing.

Something we did years ago at AST Research was to insure that the 
shielded Ethernet connector ports (when we started indlcuing them) were 
well grounded with a springy metal EMI gasket. IIRC, that is actually 
violating of the Ethernet standard, since we uses shielded twosted pair, 
and it allows equipment of different ground potentials to be connected 
to each other, but that was what we had to do to meet Part 15. Everyone 
uses that technique to ground I/O ports nowadays, but I had had to 
insist on it a number of times back at Tandy and spent some time arguing 
for fingers around board slots, too.

Cortland
KA5S