Paul.
I checked your build posts and noted you are using a metal watertight box lid...in my opinion radio doesn,t like metal boxes..screws up the signal etc and you may have some earthing issues with the electrical parts mounted onto the metal lid which when wet will earth everthing out, I always use clear poly carb lids, i noted mankster has done away with his metal lid too for a poly carb lid, plus you can always see whats going on inside too. Worth a check
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