You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
The Feb 2025 Radioddity Giveaway Results are In! Click Here to see who won!

Reply to thread

Message

Bob: You are correct in the 129 inches being the circumference of the loop. Sorry about my mistake. I'm only using the analyzer on the loop to get me in the ballpark since I know the loop simulates an electrical 1/4 wave. Although it certainly does resonate lower in frequency when removed from the main radiator and placed over a ground plane.

My method of testing automatically takes into consideration conductor sizes on this frequency since I peak gain with a field strength receiver. In the past I only took the time to do this for the FM band and estimated the scaling to CB on the few 11 meter models I modified. As you see I am going for the same accuracy on 11 now.

If you didn't expand the circumference of the loop before you experimented with the radial length, this explains your results. The cone section on the Vector is probably a little on the short side in terms of wavelength to begin with. The key here is to provide more of the length in the loop so that we can increase the angle simultaneously. That has a bigger effect but requires you make a bigger loop first. Then you will see the extra gain when you shorten the radials.

As a last note, I don't think the gamma has been changed on the new Vector.

<blockquote data-quote="Shockwave" data-source="post: 156325" data-attributes="member: 10882">Bob: You are correct in the 129 inches being the circumference of the loop. Sorry about my mistake. I&#039;m only using the analyzer on the loop to get me in the ballpark since I know the loop simulates an electrical 1/4 wave. Although it certainly does resonate lower in frequency when removed from the main radiator and placed over a ground plane.My method of testing automatically takes into consideration conductor sizes on this frequency since I peak gain with a field strength receiver. In the past I only took the time to do this for the FM band and estimated the scaling to CB on the few 11 meter models I modified. As you see I am going for the same accuracy on 11 now.If you didn&#039;t expand the circumference of the loop before you experimented with the radial length, this explains your results. The cone section on the Vector is probably a little on the short side in terms of wavelength to begin with. The key here is to provide more of the length in the loop so that we can increase the angle simultaneously. That has a bigger effect but requires you make a bigger loop first. Then you will see the extra gain when you shorten the radials.As a last note, I don&#039;t think the gamma has been changed on the new Vector.</blockquote>

[QUOTE="Shockwave, post: 156325, member: 10882"] Bob: You are correct in the 129 inches being the circumference of the loop. Sorry about my mistake. I'm only using the analyzer on the loop to get me in the ballpark since I know the loop simulates an electrical 1/4 wave. Although it certainly does resonate lower in frequency when removed from the main radiator and placed over a ground plane. My method of testing automatically takes into consideration conductor sizes on this frequency since I peak gain with a field strength receiver. In the past I only took the time to do this for the FM band and estimated the scaling to CB on the few 11 meter models I modified. As you see I am going for the same accuracy on 11 now. If you didn't expand the circumference of the loop before you experimented with the radial length, this explains your results. The cone section on the Vector is probably a little on the short side in terms of wavelength to begin with. The key here is to provide more of the length in the loop so that we can increase the angle simultaneously. That has a bigger effect but requires you make a bigger loop first. Then you will see the extra gain when you shorten the radials. As a last note, I don't think the gamma has been changed on the new Vector. [/QUOTE]

Top Bottom