counterpoise length

[1iwilly]

Time to experiment again using a Myantenna 40-10 56.1 and a 1.1 current choke. The only bands of interest are 40, 20, and 15 meters. The antenna will be used in an inverted V with the apex 30 ft above ground. I'm trying to find out what size coax jumper to use as the counterpoise between the Unun and 1.1 balun. Should I use a 6 ft or 9 ft jumper?

 

[HarryUSA]

Your UnUn probably has a counterpoise lug on it, and if it doesn't you can simply
attach a wire using a stainless steel hose clamp the the PL-259 and place it at a right angle to the coax and the feedpoint of the antenna. You can then experiment with the length since it sounds like your UnUn will be near ground level. Also, you shouldn't need a BalUn in-between the UnUn and the coax, you just need a choke at where the coax goes into the UnUn, that will force your counterpoise current to use only your counterpoise wire.

 

[binrat]

For a 40-10 EFHW use 6' between transformer and the 1:1 balun. Hint, keep the transformer low.

 

[secret squirrel]

I set one up before in my Subaru Forester, the square body type. I just used 18 feet of coax, RG 8X, attached the shield only to antenna mount. I do not really know if I accomplished anything other than it seemed to reduce static. It was a cheap experiment.