I am looking forward to getting one to work "no tuner". To date, each I've tried has been "close", but never tuner free.
I've been running a random endfed on the base as I was using a tuner anyway.
Given your advice about winding, or unwinding a wrap of wire from the toroid for fine tuning a band, what prohibits adding a wrap or two, then putting tap points across the last five wraps for a quick change setup?
Your thoughts...? Anyone...?
I am going to do it and see.
I did see something about that on the net and also using a variable capacitor across the input. I tend to add or remove turns when tuning for lowest SWR in a single band EFHW.
I have used the following criteria when using end fed antennas.
Please take into account that anything conductive nearby the antenna will serve to detune or tune the antenna to a certain degree. They really need to be in the clear. Raising and lowering the transformer above ground will affect your SWR readings. For best results try to get the transformer in the clear and 4m or so above ground.
For 80m to 10m use a 49:1 ratio and you will be in the ballpark. For 160m and 80m only, you can try a 64:1 ratio which has 3 turns on the primary and 24 on the secondary.
The outer shield of the coax is part of the antenna system (whether we want to admit it or not.) For half wave end fed antennas it is said that 0.05 wavelengths of counterpoise is enough. So I always place a choke 0.05 wavelengths in the coax down from the transformer for the lowest band in use. That works wonders to keep RF out of the shack and really makes tuning a lot easier. I have not tried grounding the transformer. People have said it helps performance.
Tune it to 14.2mhz by adjusting the wire length.
To bring in 10 and 15m add the 6 turns on 1" a diameter former in the antenna wire, about 2m from the Transformer.
How you lay out the antenna also determines it's effectiveness. Sloping or vertical or inverted V works well.
Its a half wave multiband antenna. CBers and Hams have been using them with great effect on 11 and 10m for years. they work great on the other bands too!