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

Download in a few seconds program MIDLOAD and run immediately.

It will soon tell you where or who is going wrong. Coil length and length
of wire beyond end of coils are fairly critical. It's a good idea to use
thick wire on the coil, or use tube on the higher HF bands.
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Regards from Reg, G4FGQ
For Free Radio Design Software
go to http://www.g4fgq.com
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"VE8AE Andrew" wrote in message
om...
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