The beginning 1. Just modified the Spitfire to 4SQ. Each vertical had 2 elevated radials at 3m high

The beginning 2. I tried many feed methods, this visible solution is a Christman/Lewallen combination

The beginning 3. You can see the temporary L-C elements at the phase-shift box


This is a Hybrid Coupler. It provides the necessary phase-shifted currents to each vertical elements

This is a Lewallen system. The CW and SSB segments are switchable by relays. This way the available bandwith is about 80- 80 kHz with excellent directivity!

Quarter wave feed lines made of outdoor TV coaxial cables, with current balun chokes at their ends



Individual vertical with two, 5m high elevated radials now. The resonant frequency can be remote switch to 3.520 and 3.750 kHz

Preparing the first cross arm still on the ground. The ladies want to help us building a 4 Square. Fight for the priority ... :)

The first arm is already fixed at 25m high


We set the second arm now

Isn't it nice?

You can see the shematic of my 4 Square by the MMANA modelling software



This is the predictable vertical and horizontal pattern of the 4SQ

Control unit in my shack

This old buried radial system -from the Spitfire times- makes really better ground conductivity under the 4SQ


Very first of all, it must be set the resonance of each individual vertical (3520 and 3750 kHz). It is very easy with MFJ-259B

Testing the Lewallen feed method again. I could obtain very impressive directivity vs. HC

I am registrating all the parameters, parts values



A new chapter after 4 SQ building ... :)