04-08-2008, 05:15 PM
Bill Fulling Wrote:hI EXRAY,Gotta disagree with you on this one,in the 1937 Philco models that used the same antenna,the primary antenna windings were center tapped to ground and the antenna itself was switched to "T" configuration on the BCB and operated as half wave dipole on SW.The exact resonant frequency of the antenna was dependent on how long you cut each leg-usually about 12 Mhz (25 meters).So why put a dipole for 40 meters in length when one for 20 would do?(for rx purposes only!).I can see your take on the counterpoise,but I'm not talking verticals here.
If its a question of length then they were possibly operating the dipole at both 1/2-wave and 3/2-wave lengths. Using a freq 12 Mhz (25 m) just for example...a dipole of 37.5 meters in length will work as well if not a tad better than one of a 12.5 m length PLUS the 37.5 m one has the advantage of working at 4 MHz (75 m wavelength) as well.
I have no idea if thats what they had in mind but a dipole would work that way.
-Bill