[RFI] A quick Question about CMC placement

[Jim Brown]

Grounding and bonding is NOT about an earth connection, but rather the 
proper bonding together of all earth electrodes as required both by 
Electrical Codes and good engineering practice, the proper bonding 
together of all equipment within the station, and the bonding of the 
common point of those bonds to the earth electrode system.

Proper grounding and bonding serves at least three important purposes. 
Most important, lightning protection. Second, minimizing the extent to 
which interconnecting cables connected to equipment act as antennas when 
connected to equipment with Pin One Problems. Every rig I was able to 
study in booths the last time I was in Dayton and later at Visalia had 
Pin One Problems at every connector except those for transmitting 
antennas. Third, it minimizes power system hum (60 Hz) and buzz (triplen 
harmonics of 60 Hz) that results from leakage currents (line to green) 
on power wiring, and another mechanism too complex to discuss here. If I 
can find it on my computer, I can send a pdf of an AES Paper by Bill 
Whitlock, like myself, a Fellow of the AES and a principal author of 
nearly all AES Standards on EMC.

73, Jim K9YC

On 6/28/2021 10:45 AM, David Eckhardt wrote:
> There is no true "ground" for RF fields.  Only returns.  The space 
> station doesn't require a "ground" for comms to/from earth stations.  
> The Crab Nebula does not require a "ground" to fill deep space with 
> copious amounts of RF energy.   I disagree with your statement:  " That 
> indicates a problem with grounding and bonding ".
> 
> There is absolutely no way I could establish an adequate "ground" in my 
> decaying upper Permian / lower Triassic mudstone.  And, what's more, I 
> do NOT have "RF in the Shack".  Any good installation should have a lot 
> of RF in the shack if the antenna is operating as intended, just not 
> experiencing RF 'bites'.