[Amps] The Pin One Problem

[Jim Brown]

On 6/8/2013 10:03 PM, Larry Benko wrote:
> Pin 1 problems can cause RFI but I don't think they are a major cause 
> compared to common mode cable currents and large differential cable 
> currents which get partially converted to common mode currents via 
> imbalance.  I don't believe that FCC Part 15 specifically tests 
> susceptability but many other standards do. 

Although this is a topic for a different email reflector, I strongly 
suspect that Pin One Problems are a major cause of egress, including, 
for example, CATV cables. We know that all passive networks work in both 
directions, although their transfer ratios may be different, depending 
on both internal and external impedances. Any Pin One Problem that lets 
RF into the box is likely to let RF out of the box if there is a source 
inside.

And you're correct, there is, as far as I know, no FCC requirement for 
testing with cables attached, nor for much below 30 MHz.  I hear from my 
AES Standards colleagues in the UK that their EMC regulations ARE slated 
to begin requiring compliance of complete systems (that is, with 
interconnections).  That would be a VERY good thing.

73, Jim K9YC