After spending next to four weeks off the air due to the new antenna system suddenly going high VSWR 6:1 the guys, Dave and Fred, finally managed to get the system down for us to check where the fault lay typically when I test the VSWR before taking it down the fault had cleared on its own.
Originally the system gave a VSWR of 1.1:1 until it rained when it went high, now since that point it hasn't rained so I can only assume during the intervening period whatever had got damp had since dried out.
All the connectors looked dry with no indication of water ingress seen, the coupler was also bone dry. The powabeams use an ABS moulding to fix the driven elements to the beam and this is glued shut during manufacture so it's impossible to open without destroying the moulding in the process.
We put more rubber sealant on around the Powabeam ABS moulding, the end caps on the coupler and around the N-Type sockets on the coupler as well I also wrapped self amalgamating tape around the ends and over the centre hole that gives access to the middle socket.
We then put the system back together with all joint resealed with amalgamating tape it now looks like it should take being dipped into the sea before it leaks but only time will tell.
The only modification we made was to make the quarter wave chokes as depicted on the Powabeam website originally we put the loop over the back of the beam which certainly worked however both Dave and I have Powabeams and switched the recommended way of creating the choke which we both agree seems to give a better response.
I used the system again in this weeks 2m UKAC and it worked flawlessly so fingers crossed it'll carry on working.
Again a big thanks to Dave M1DNJ and Fred for doing all the manual labour.
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