4:1 BalUn

I’ve been wanting to built a good 4:1 BalUn as part of the never ending project that is my HF antenna system for some time and today, I finally got around to the job. This is a “true” 4:1 Current BalUn that is wound as two separate 1:1 current baluns and then placed together to create the 4:1 ration. Any 4:1 built on a single core that claims to be a current BalUn is lying and is actually a Voltage BalUn! Continue reading “4:1 BalUn”

Ladder Line Surge Suppressor

I usually get static build up on my HF doublet due to sand particles (I live above the beach) in the air so have been thinking about a way to bleed off the static and provide some protection to my TS-590SG. After a little research, I came up with this, a lightning arrestor/static bleed device that provides a permanent path to earth for DC whilst allowing RF to pass and providing protection from nearby lightning strikes. Continue reading “Ladder Line Surge Suppressor”

SGC-230 relay replacement

A common fault on the SGC range of antenna tuners is a reduction in receive performance as they get on in years. This can be attributed to contamination on the relay contacts since SGC stoped using fully sealed relays. Any small condensation inside the tuner makes it’s way into the relays and causes contamination on the contacts as they are hot switched. The best thing to do is to replace all 26 relays with new units…

Continue reading “SGC-230 relay replacement”