I think I can see the problem!

I have 2 VHF/UHF antennas outside of my flat for RX and TX. The Nagoya MAG-77EL-WH, which sits on the floor and I use primarily as an RX antenna for my digital scanner to pick up local signals. To say it’s on the floor it works quite well really and does everything I need it to do.

Then there is the Diamond D-130 Discone Wide Band RX/TX antenna mounted on a 3 meter pole which I use with my Yaesu FTM-500 primarily for TX on 2m and 70cm bands. Again it works really well.

About a week ago I noticed a sudden and dramatic drop off in reception of my local repeater GB3NF and my SWR had shot through the roof. Switching the FTM-500 over to the Nagoya and the problem went away. Confirming the problem was an antenna /coax problem given there is nothing on the Discone to go wrong. If it’s there it will work.

This morning I managed to get out to the Diamond D-130 Discone antenna and strip it down to see if I could find the problem. I’m very pleased to say I found it almost instantly. The coax had fallen out of the back of the PL259 and the centre pin was sitting in free space. I think some people describe this as and “air bridge”!!

Popped the coax back through the shack window, sat down at my desk and refitted the PL259 but this time added substantial amounts of hot glue and tape to reinforce the joint. Didn’t look nice but it was solid.

Once back outside I reassembled the Diamond D-130 Discone to it’s pole and also added a number of cable ties to carry the not unsubstantial weight of the coax. These ties were there before but not as tight as they needed to be to take the weight of the coax (lessen learned).

Back in the shack and everything is reconnected and I’m happy to confirm that reception of GB3NF is fully restored and SWR levels are back down to 1:1 on both VHF and UHF.

Not bad job to say it all took place before 9am!!