Do any of you Guys use the 2M Big Wheel, and if so where is it resonant?
My one is now resonant at 148 MHz with a reasonable SWR, but 1:2.5 at 144.3 MHz.
I took it down to clean/maintain, and may have disturbed something, I don't imagine the matching stub would influence resonance?
I have emailed Wimo, but from past experience they haven't bothered to reply.

Stewart

It should be 144 to 146 by default.
And around 1.8:1 either end.
The tuning stub will of-course alter tuning / resonance.

This is from a home built one I made before wimo started making them.
Wimo's version shouldn't be dissimilar.
If it worked previously OK, and has gone high, then I would check the stub connection inside the black box.

The major part of tuning with these was with the element lengths.
As far as I remember the three elements are parallel to 35 ohms and the stub transforms to 50.

I stripped-down the ant. again, & found moisture in the hub.
I thought I'd sealed it adequately, but obviously not.
Anyone know what sealant they use?

Anything that stops water.
I've used silicon sealant , mastic or silicon grease to cover the exposed joints.
Or self amalgamating tape round the outside.

I generally only use the tape on coax connections and the silicon sealant on permanent joints.
The silicon grease is great to smear on anything and is easily wiped off with a rag.

I actually did use Dow Corning 111 silicon grease last time, but moisture still got in. I'll try using a bit more, then maybe use 3M liquid rubber outside the hub. Only problem is the liquid rubber is a bugger to remove if it happens again.

Cheers Mark.