[Elecraft] OT: Inverter type generators used for FD?

[Jim Brown]

On 6/30/2017 6:19 AM, Fred Moore wrote:
> I also have found no reason for any type of filter with Honda's..
> additional savings.  Also note that one brand the noise hash was being
> emitted directly from the generator not the power line, a filter won't
> fix that one.

This will, of course, depend on how close the generator and its power 
wiring is to antennas. It also depends on the other RF noise at the 
site. We operate FD, CQP, and 7QP from places where there is NO local 
noise other than what we bring with our gear, so it's common to see 
S2-S3 on our K3 meters. If you're somewhere with S6 background noise, 
you're less likely to hear noise from the generator. In 7QP, we operate 
portable from multiple locations on county lines, so we have two 
generators mounted on the bed of the pickup truck that pulls our 
contesting trailer. This puts the generators right underneath our 
antennas, which makes filtering critical.

The mechanism here is that noise is conducted onto the power cable from 
the generator as a common mode signal, which radiates into our antennas. 
That's why the common mode choke is needed, and why it works.

73, Jim K9YC