Inexpensive Mag Mount Weatherproofing
I’ve had a love/hate relationship with the cheaper magnet mount manufacturers like Browning and Tram since I became interested in radio back in the scanner days many years ago. My problems seem to always arise after a long period of rain which happens to be 6 months of the year here in the southern US. Since becoming a HAM I’ve had even more issues since water and transmitting don’t mix well at all. After all the issues I’ve had with these NMO magnet mounts I believe I can make them truly waterproof and without issue. The NMO magnet mount I’ll be using is branded under the Browning name (the Tram version is identical) and came from Amazon for $21.99.
The base comes with a rubber cover that works great for 1-3 months before the weather causes it to become a nice bowl which holds water inside the antenna mount instead of keeping it out. Under that is a thin metallic layer of decal material designed to protect the magnet and internal base of the antenna mount. The decal material also works great for a few months but eventually rusts and fails due to the water standing in the base.
Cutting the center out of the metallic decal will reveal the 2 nuts that attach the NMO mount to the base. The brass phillips screw is new to these and holds the cover onto the magnet in the event the glue turns loose. The older versions of this mag mount did not have this extra screw and relied solely on the glue used to attach the magnet to the base.
The fix, Gorilla Epoxy!
After removing the NMO mount I inspected the solder joint on the center conductor and the crimp on the outer jacket, both looked and tested with a meter. I considered soldering the outer jacket to the brass crimp connection but decided against it since the contact was very good and once the epoxy has set there will be no movement possible. Once everything was verified to be ready I filled the NMO connection with the Gorilla Epoxy.
The epoxy claims to set in 5 minutes and be fully cured in 8 hours however I’m going to give this 24 hours or more before reassembling and putting into service. I’ll have to test and see if this works over the next several months but as long as the epoxy doesn’t break down I believe this will be a permanent fix.