I am copying a design from the PAC -12 from KA5DVS. Now I am using
some different materials but using same design. Using what I had on
hand. I calculated his laoding coil for 40M to have about 8.68 uh
inductance, so I used some 1/8" tubing I had for lower losses. I
calculated my coil for 8.87uh by formulae, as it is 8" long and had a
radius of .75" with 37 turns. WHich should all work out. But I put
antenna outside and it only has lowest swr at 13.4 MHz or so. What the
heck is wrong? It should be good around 7MHz same as other design. I
know I must be missing something , but kids are driving me crazy and I
can't think! Any help is appreciated, thanks.
Andrew VE8AE