17-01-2018, 03:18 PM
G'day Hayden,
You may need to add some more ferrites close to the feedpoint for them to be effective at stopping common mode currents. Try and get those additional 3 ferrites up with the other one at the feedpoint if you can.
It really does depend on what/where you read it, but some sources say above 1k at the required frequency, while I've also read recommendations of more than 5k !! But I do think that 250ohm at the feedpoint isn't enough, so the 200mm tail could well be radiating and throwing the pattern out.
Another method is a pawsey stub, but can be narrow banded.
I don't have the part numbers and specs on me at the moment, but I plan on placing about 6 or 7 ferrites at the feedpoint of the 2m OWL yagi, and 4 or 5 for the 70cm LFA.
Cheers
Jayson
P.S> the link to your blog site isn't working
You may need to add some more ferrites close to the feedpoint for them to be effective at stopping common mode currents. Try and get those additional 3 ferrites up with the other one at the feedpoint if you can.
It really does depend on what/where you read it, but some sources say above 1k at the required frequency, while I've also read recommendations of more than 5k !! But I do think that 250ohm at the feedpoint isn't enough, so the 200mm tail could well be radiating and throwing the pattern out.
Another method is a pawsey stub, but can be narrow banded.
I don't have the part numbers and specs on me at the moment, but I plan on placing about 6 or 7 ferrites at the feedpoint of the 2m OWL yagi, and 4 or 5 for the 70cm LFA.
Cheers
Jayson
P.S> the link to your blog site isn't working