[RichG]

Well, here is an update of my proof-of-concept loop antenna.  In order to try and match the loop impedance to the radio, I inserted two 1mH chokes in series with the antenna connections.  One choke to the antenna connection and one choke to the ground connection. Impedance matching would be ideal, but this was more of a case of trying to increase the loop impedance. I do notice an increase is signal strength, unfortunately there is also in increase in the static but it's not outrageous.  It is extremely unusual for me to get Fort Collins, Colorado on 10MHz in the daytime.  But WWV comes in quite strong, and it's nice to know the clock on my wall is only 15 seconds fast!!  Just as another 'what if' test, I shorted out the choke that went to ground and I lost WWV immediately.  On the AM band, shorting out the choke to ground reduces the signal strength by quite a bit.  I tried adding a third choke in series with the antenna connection but didn't really notice any major changes.  I'm thinking the two 1mH chokes may be the best I can do for the time being. I think this is a case of increasing the loop impedance by a fixed amount being okay on one band but not the other bands.  I may play around with adding a capacitor to the mix to see if that makes a difference.  If anyone has suggestions, I'd like to hear them.  As you can probably guess, my antenna skills are a bit lacking!
Thanks everyone!
Rich