Topband: Waller Loop

[David Cole]

I have built a Waller Loop to the dimension from information on the internet, the loop is vertical and mounted on a tower at 30 foot. My problem is I cannot get any front to back. I have rewound the transformers and made two phasing lines - all show now difference, I checked the 180 degree phase shift with my scope by feeding the AIM 2180 constant signal. All looks good.
I then decided to build a second Waller Loop using all non metallic tubing - excellent all works fine and very acceptable front to back. On the second working loop I replaced the support pole with aluminum - no change and still excellent front to back.My only conclusion now is that the two loops are coupled by the 26 foot aluminum boom. I have sufficient size and strength glass fiber pole which I intend fitting in the center of the current boom, this will put a distance of 7 feet between the boom ends and hopefully reduce any coupling. Has anyone had any experience similar to my self and if so what is the answer?My test to prove the front to back was to beam both loops at 300 degrees, the forward gain in the receive path was equal - however the difference when looking at stations of the back was from S7/8 on the no F/B loop to in the noise on the working loop. I am sure, as I am so involved, I am missing something help!! Dave g3rcq