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Homer, I have a A99 on a insulated 12' mast along side my AstroPlane at 45' to the tip. When conditions are good and quiet the AP is typically very quiet and hears better that some of my other antennas and for sure the A99 when it is raised up 30'-40' feet. However with the A99 lower and conditions being a bit variable at the present time, the A99 acts more or less as you describe your Qv4k. I have my antennas on a switch box and that makes this comparison easier to perceive. Were you using a switch box?

I'll also mention that in my modeling the Sigma4/Vector my pattern reports indicate the gain goes down remarkably when the mast is insulated...with the angel remaining the same. This might be something to consider in your evaluation of your Qv4k vs. the 5/8. I can't model a coaxial choke in my models, but I would think its use would be a good idea with this antenna. The model suggests that there is noticeable currents flowing on the support mast, and that may be why insulating vs not insulating shows such significant gain differences. I can't explain why that is, but that is what the reports show. As something to consider, I'll post the patterns for gain and angle below.

[ATTACH]3719[/ATTACH]

[ATTACH]3720[/ATTACH]

Notice also how the affect seems to press down on the pattern for the non-insulated mast setup. In all my models this insulating idea really makes a big difference in gain with my antenna with a 1/4 wave radiator, which really needs an effective ground plane. This also seems to hold true with the 3/4 wave Sigma4/Vector, which I believe really needs a ground plane as well. The 5/8 wave does not seem as ill-affected when I insulate its mast however. This business surprises me, because I would have thought different, but this is what I see in the models.

<blockquote data-quote="Marconi" data-source="post: 243019" data-attributes="member: 903">Homer, I have a A99 on a insulated 12&#039; mast along side my AstroPlane at 45&#039; to the tip. When conditions are good and quiet the AP is typically very quiet and hears better that some of my other antennas and for sure the A99 when it is raised up 30&#039;-40&#039; feet. However with the A99 lower and conditions being a bit variable at the present time, the A99 acts more or less as you describe your Qv4k. I have my antennas on a switch box and that makes this comparison easier to perceive. Were you using a switch box?&nbsp;I&#039;ll also mention that in my modeling the Sigma4/Vector my pattern reports indicate the gain goes down remarkably when the mast is insulated...with the angel remaining the same. This might be something to consider in your evaluation of your Qv4k vs. the 5/8. I can&#039;t model a coaxial choke in my models, but I would think its use would be a good idea with this antenna. The model suggests that there is noticeable currents flowing on the support mast, and that may be why insulating vs not insulating shows such significant gain differences. I can&#039;t explain why that is, but that is what the reports show. As something to consider, I&#039;ll post the patterns for gain and angle below.&nbsp;[ATTACH]3719[/ATTACH]&nbsp;[ATTACH]3720[/ATTACH]&nbsp;Notice also how the affect seems to press down on the pattern for the non-insulated mast setup. In all my models this insulating idea really makes a big difference in gain with my antenna with a 1/4 wave radiator, which really needs an effective ground plane. This also seems to hold true with the 3/4 wave Sigma4/Vector, which I believe really needs a ground plane as well. The 5/8 wave does not seem as ill-affected when I insulate its mast however. This business surprises me, because I would have thought different, but this is what I see in the models.</blockquote>

[QUOTE="Marconi, post: 243019, member: 903"] Homer, I have a A99 on a insulated 12' mast along side my AstroPlane at 45' to the tip. When conditions are good and quiet the AP is typically very quiet and hears better that some of my other antennas and for sure the A99 when it is raised up 30'-40' feet. However with the A99 lower and conditions being a bit variable at the present time, the A99 acts more or less as you describe your Qv4k. I have my antennas on a switch box and that makes this comparison easier to perceive. Were you using a switch box? I'll also mention that in my modeling the Sigma4/Vector my pattern reports indicate the gain goes down remarkably when the mast is insulated...with the angel remaining the same. This might be something to consider in your evaluation of your Qv4k vs. the 5/8. I can't model a coaxial choke in my models, but I would think its use would be a good idea with this antenna. The model suggests that there is noticeable currents flowing on the support mast, and that may be why insulating vs not insulating shows such significant gain differences. I can't explain why that is, but that is what the reports show. As something to consider, I'll post the patterns for gain and angle below. [ATTACH]3719.vB[/ATTACH] [ATTACH]3720.vB[/ATTACH] Notice also how the affect seems to press down on the pattern for the non-insulated mast setup. In all my models this insulating idea really makes a big difference in gain with my antenna with a 1/4 wave radiator, which really needs an effective ground plane. This also seems to hold true with the 3/4 wave Sigma4/Vector, which I believe really needs a ground plane as well. The 5/8 wave does not seem as ill-affected when I insulate its mast however. This business surprises me, because I would have thought different, but this is what I see in the models. [/QUOTE]

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