off centre fed wire antenna

hi!

I want to build a "long wire" type of antenna - really an off-centre fed antenna - 34m one side 7 m the other (approx). According to MMANA this should give me a feeding point of 180 ohms and a very adequate gain and direction of 14MHz and 7MHz. The wire to be used is 2.54mm insulated household wire (#10 wire).

Questions:
1. I am thinking of building a home-built ladder line for this antenna made of the same wire (#10 wire - 2.54mm = 1/10th of an inch diameter copper wire) about a pencil thickness apart (roughly 1/4") which I think should give me 180 ohms or near that. Can somebody confirm this please?

2. I am not sure which kind of toroid to use. If I superglue 2xFT240-52 toroids together and wind 5 turns primary and 18 turns secondary (to get the 50:180 transformer needed) on this superglued toroid core, using the same #10 wire, how much wattage roughly will this transformer withstand?

thanks to all who will answer and best 73s from
Joe, 9H5JO

Joe,

Amidon and the other toroid core manufacturers should have data sheets for their products which list power saturation curves as a function of frequency. From this it should be easy to determine transformer heating for a given frequency, winding construction and applied power level. There should also be a "do not exceed" value noted as well.

As far as ladder line spacing goes, I'd use EzNEC or a similar antenna modeling program. There may be an online version that you can use.