There is no doubt, end feds work!
Whether no-tune, multiband, end feds work is still debateable (In my opinion).
Last night I built a 20m end fed in particular to attempt a RaDAR to RaDAR QSO with Tom G0SBW on the weekend.
On receive, I have found when the best signal strength is where the capacitor plates are unmeshed then you’re no where near resonance on the LC low pass filter tuned circuit. I pulled this toroid out of a MFJ945e mobile tuner which I am modifying as a Fuchs style tuner and have no idea of the type but it is a red toroid which obviously should be suitable.
I started off with 26 windings and ended up at around 13 and found resonance with the capacitor half meshed. With a SWR meter in line I came close to zero SWR and using the FT-817’s built in SWR indicator it was confirmed! Full power output from the 817.
Looking forward to using my 10m fibreglass telescopic mast, this end fed (10.1m wire) and my battery powered (7 A/Hr SLABS) FT-897d to make contact with Tom. He recently had a QSO with Namibia so conditions may be favourable!
The 20m end fed circuit is very simple, I have a 40m end fed too which has proved itself over and over again!.
73 de Eddie ZS6BNE