The first thing I did was gather the parts. I used LNR-400 coax for the main loop. Some 10 gauge wire for the small loop and some RG8 for the coax to the rig.
I also purchased a variable capacitor from Midnight Science - it is a single gang. I probably should have purchased the dual gang - and probably will - more on that later. I also picked up the reduction drive from them.
Here is how it looks right now all set up:
It is a really slick setup - the grey pipe is simply plastic electrical conduit - everything is simply attached using wire ties.
Inside the "black box" - the air variable capacitor, reduction drive and coax connectors for the loop coax. If you look closely you will see that I ran a short wire from the center to the ground on the coax connectors.
It is all fine and dandy BUT I can't get the darn thing to tune! At first I thought it was the feed loop not being built correctly - and I was right! However, after rebuilding the feed loop the thing still won't tune.
I can almost get it tuned on 10 meters - down to about 3:1 - but the capacitance introduced by my hand turning the capacitor is horrible. I have read that if you use a 2 section capacitor this problem is reduced. Once I can get it working with this capacitor I might invest in a 2 gang.
I really think it comes down to the feed coax at this point. There is just not much else that could keep it from working. I am going to rework the connector and see if that fixes it.
Right now I have it all set up looking really cool - but it does absolutely nothing! :)
Burke. Did you ever get it working?
ReplyDeleteAny update?
ReplyDeleteAny update?
ReplyDelete