I ran some more tests over the weekend. My antenna was a 50' high, 50' long
dipole center fed with twin feed through an antenna tuner with an internal
4:1 balun. With the generator running and my Icom 746/PS15 connected to it
(through the cabin wiring), my noise level on 20M is about S9. When I
connect the 746 to my truck battery the noise level drops only slightly to
S8+. When I turn the generator off, the noise level becomes almost
non-existant with just atmospheric noise. Unfortunately, I forgot to check
the noise level when the generator is running but disconnected from the
cabin. I'll try that this next weekend. Also, the noise level is
definitely higher at some frequencies. At this point I'm pretty sure that
what I have is common-mode noise that is being radiated by the cabin wiring.
If I'm correct, then I should see lower noise levels when the generator is
running but unplugged from the cabin. Now i just need to decide whether to
purchase a commerical RFI filter or build one with a couple of toroids.
Thanks again for all of the helpful suggestions.
Clay W7CE
----- Original Message -----
From: "Clay Curtiss W7CE" <w7ce@curtiss.net>
To: <rfi@contesting.com>
Sent: Friday, March 25, 2005 9:55 AM
Subject: Re: [RFI] Honda Generator RFI
> Thanks to all for the very helpful replies. I'm heading up to the cabin
> this weekend and will do some more experimenting to determine the noise
> source. Then I can determine the best way to quiet things down. I also
> hope to put up a dipole that is center fed with twin feed through a tuner.
> It will be interesting to see if that is quieter than the end fed wire
that
> I'm using now. I'll post the results on Monday.
>
> Clay W7CE
>
> _______________________________________________
> RFI mailing list
> RFI@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|