Hi Simple answer - yes.
My observation over the years is that your typical roof absorbs quite a bit of RF starting way below GPS frequencies. My *guess* is that shingles are a bit lossy. Shingles + moisture more so. Shingles + dirt + moisture even worse. I also believe that plywood suffers the same way. Also consider that you have things like flashing, ridge vents, and gutters involved. Somewhere below 2 MHz or so things begin to get less crazy. I’ve spent a lot of time putting antennas up in a lot of attics and then moving them outdoors. Bob On Aug 28, 2014, at 9:30 AM, Bob Stewart <[email protected]> wrote: > Hi Attila, > > > Is wood, nails, and asphalt shingle really that big of a problem at these > frequencies? The antenna is within 2 ft of the highest point of the roof. > > Bob > > > > ________________________________ > From: Attila Kinali <[email protected]> > To: Bob Stewart <[email protected]>; Discussion of precise time and frequency > measurement <[email protected]> > Sent: Thursday, August 28, 2014 8:15 AM > Subject: Re: [time-nuts] Practical Survey-In Accuracy? > > > On Sat, 23 Aug 2014 16:38:42 -0700 > > > > Bob Stewart <[email protected]> wrote: > >> Given that my antenna is just a puck at the peak of the attic (never got >> around to adding the DIY choke-ring) > > A choke ring will not help you much in the attic. You already have lots > of reflecting and refracting surfaces/volumes above the antenna. > Unless you get to the top of your roof, i wouldn't bother adding a choke ring. > > > Attila Kinali > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
