Why would stainless steel provide different performance? Can you use
regular mild steel for the angle iron bracket? Maybe paint it so it
would not rust?

If you do change the element size, how do you determine the proper
spacing?

I appreciate your help! I like the design of the antenna and its
simplicity.


At one time I had a chance to acquire a large number of Stainless Steel CB
whips, cheaper than the cost of aluminum.
I used 8 of them to make a 4 element Yagi just like our regular 146-4S.
It works, SWR is low, but it just does not work as well as the aluminum
elements.
Used a couple to make an OSJ, because of the smaller diameter, the spacing is
closer to get it to match But like I said there was a very noticeable drop in
performance. I really wanted it to work, would have been a good market for
them for mounting on 18 wheelers.
(Don't ask, I won't sell ether of them.)

As for making the bracket out of steel, Why ? it's harder to drill, harder to
tap. The 3/16" stress aluminum angle is a lot stronger than it needs to be.

As for determining the proper spacing, if you know the exact impedance
of the 1/2 wave, there is a formula for figuring the diameter & spacing.
Easier to just adjust the spacing for lowest SWR.

Unlike other types of J-Poles the OSJ does Not need a balun or choke.
It was designed for direct connect to coax.

73 Al Lowe N0IMW
Arrow Antenna