I have know a ham that wrapped his extra feed line on the wall in the radio
shack.
Feed line is nothing but in series inductance. There is a lot more involved.
So keeping it simple and to get you going FEED LINE IS NOTING BUT IN SERIES
INDUCTANCE. Take two identical coils. Space turns 0.077 inches if running a KW
other wise less for lower power. You can mount the the two coils at least 4
inches apart. If they are closer no big deal. The idea behind it is to get
your friend on the air and going.
Cut the length of the wire to the length of the feed line thats needed. So if
you have 10 feet of feed line and you need 65 feet, cut two pieces of wire at
55 feet. You can make the coils longer and you can tap the coils at any point
you wish.
Now if you put a piece of twin lead at the feed point end of the coil say to a
balun you must also add that length to the total length.
You have some adjustment for SWR by changing the length of the ladder line or
the coil taps. Remember when adjusting the coil taps, adjust the taps the same
number of turns, in other words keep the taps se-metrical or equal to each
other.
Keep The Faith, Jim K9TF/WA9YSD
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