One of the things I accomplished while Chuck, W1HIS was here is to address the FIOS battery backup charger RFI that was present in my background noise. Without a doubt, this single device puts out more RFI than any other device I have encountered. The Direct TV HDDVR was bad enough but this one takes the cake. I had it RFI’ed but certainly not well enough. I had put several binocular Mix 31 chokes on both input and output but felt I was in need a a differential line filter for the unit plus much more ferrite on the output side of things. Inasmuch as this unit is owned by the utility I also believed that to cut and splice their AC Line cable should be approached with caution-hence I never did it. However, while Chuck was here he suggested applying more ferrite to all cables surrounding the unit and all associated cables to lamps, telephones etc as these were all coupled to the FIOS battery charger through E Field coupling due to proximity. I was unable to apply more ferrite to the output side but did manage to apply much more to the input (117VAC) side of the unit. This application, together with the ferriting of the associated close proximity cables took 2 S Units of background noise out of my received noise level on 20 Meters. It also reduced my noise level on 17 Meters to almost zero. The way we check noise levels is to open up my bandwidth to 9 Khz and place the receiver in AM mode. Any S Meter readings I refer to will be done in this manner. For several years my received 20 Meter noise level has varied between S-5 and S-7 and now it has been routinely at about S 3 to S4. A rather nice improvement.
In the following picture you will see the power strip covered with ferrites. I had them on the shelf and so I just went whole hog so to speak and maxed out the coverage. I have done similar installations to all of my computer monitors in or close to the shack. Tracking local noise sources seems like a never ending chore.
Thanks for reading my Blog. Best, Chas W5PG