Antenna's that get that VOODOO Audio thru the Ether!
Posted: Thu Feb 24, 2005 10:42 pm
Well Ya'll,
If your gunna run Full Range Audio, You got to have the Signal for it.
It takes about a consistant 20db over S-9 signal to get all the Audio information into the Receiver without any ill-effects.
This takes a good amplifier with lots of headroom, and a good antenna.
We use several antennas, depending on the conditions and the distance that we're talkin.
Since these comparisons where done, we have taken down the NVIS Phased Arrays due to different problems. Storms, Strong RF Fields, etc.
Here are some results of the loop compared to the two other antennas.
The loop is now at a length of 1058 feet long, and a height of an average of 100 feet. We tried all different types and lengths of feed line and baluns. The final feed line and balun configuration was 450 ohm ladder line and a 4:1 balun at the tuner. we use this antenna on 160 - 10 meters.
The comparison antenna's are as follows:
1) 160 meter Carolina Windom used as a multibander thru a tuner. It is 268 feet long, and at a height of 100 feet. I use this antenna for 160 meters and for long distance contacts on 75 thru 10 meters due to its low angle of radiation.
2) 2ea, 20 meter 3 element Co-linear Phased arrays. These two antennas are seperated 68 feet from each other and phased together. They are at a height of 90 feet. This antenna is also a multibander used thru the tuner. We primarily use this array as a NVIS antenna for short range on 40 and 75 meters due to its very high angle of radiation on 40 and 75 meters.
We will describe how the antennas compare from band to band starting at 160 meters.
1) 160 Meters:
The loop does extremely well out past 200 miles due to its low angle of radiation. It is 2 wavelengths long at 1058 feet, this flattens the high lobes out alot flatter. This was the main reason we started with the loop long at 2000 feet. Because of tuning problems on the upper bands, we had to compromise and shorten the loop to its present length of 1058 feet.
The 160 meter Carolina Windom does better than the loop from 200 miles and closer.
The Co-linear is not operated on 160 meters.
2) 75 Meters:
The loop performs the best at long distance from 300 miles and longer.
The 160 meter Carolina Windom is also good from about 300 miles and past, but it is about 10db down from the loop.
The Co-linear is 10 to 20db stronger in signal than both the above antenna's at close range. This is from 300 miles and closer.
3) 40 Meters:
The loop performs the best at long distance from 400 miles and longer.
The 160 meter Carolina Windom is decent from about 300 miles and past, but it is about 15db down from the loop.
The Co-linear is 10 to 20db stronger in signal than both the above antenna's at close range. This is from 300 miles and closer.
4) 20 Meters:
The loop totaly out-performs the other 2 antenna's at long distance from 600 miles and longer by about 10 to 20db.
The 160 meter Carolina Windom performs well from about 500 miles and past, but it is about 10db down from the loop on the average.
The Co-linear performs fair on this band. This is the band it was desighned for. It has 6 high gain lobes which perform fair, but the Carolina windom and the loop beat it every time. We found out that this antenna has VERY high angles of radiation when used on 40 and 75 meters. That is the reason We built 2 of them and phased them together.
5) 17 Meters:
The loop totally out-performs the other 2 antenna's by about 10 to 20db, hands down.
The 160 meter Carolina Windom is decent, but it is about 10db down from the loop.
The Co-linear is a dog on this band and i don't use it.
6) 15 Meters:
The loop totally out-performs the other 2 antenna's by about 10 to 20db.
The 160 meter Carolina Windom is decent, but it is about 10db down from the loop.
The Co-linear is horrid on this band and we don't use it here iether.
7) 12 Meters:
The loop totally out-performs the other 2 antenna's by about 10 to 20db.
The 160 meter Carolina Windom is decent, but it is about 10db down from the loop.
The Co-linear is useless on this band.
8 ) 10 Meters:
The loop is incredible on this band! The angle of radiation is sooooo looooow, and the capture area is so great, that it will pick up signals that the other 2 antenna's will not even hear. The loop is at 37 wavelengths at 28.5Mc!! Another plus is that the SWR is not over 2.8 from 28Mc to 29.7Mc.
The 160 meter Carolina Windom is decent, but the loop is superior.
The Co-linear is useless on this band.
9) 6 Meters: (YES! 6 Meters)
The loop works exceptionally well on this band. The SWR is not over 2.5 from 50Mc to 54Mc.
The Carolina Windom is flat all the way thru this band and works terrific. No tuner needed.
The Co-linear is useless on this band.
10) 2 Meters:
I have tried the loop on 2 meters with decent local results, so it does radiate. The match is not bad, SWR of not more than 3.0 from 144Mc to 148 Mc.
The Carolina Windom radiates fair (especially off of the ends) on this band, and the match is good.
The Co-linear is useless on this band.
Well that is the performance of the antenna's here in the Swamps of Louisiana.
If your gunna run Full Range Audio, You got to have the Signal for it.
It takes about a consistant 20db over S-9 signal to get all the Audio information into the Receiver without any ill-effects.
This takes a good amplifier with lots of headroom, and a good antenna.
We use several antennas, depending on the conditions and the distance that we're talkin.
Since these comparisons where done, we have taken down the NVIS Phased Arrays due to different problems. Storms, Strong RF Fields, etc.
Here are some results of the loop compared to the two other antennas.
The loop is now at a length of 1058 feet long, and a height of an average of 100 feet. We tried all different types and lengths of feed line and baluns. The final feed line and balun configuration was 450 ohm ladder line and a 4:1 balun at the tuner. we use this antenna on 160 - 10 meters.
The comparison antenna's are as follows:
1) 160 meter Carolina Windom used as a multibander thru a tuner. It is 268 feet long, and at a height of 100 feet. I use this antenna for 160 meters and for long distance contacts on 75 thru 10 meters due to its low angle of radiation.
2) 2ea, 20 meter 3 element Co-linear Phased arrays. These two antennas are seperated 68 feet from each other and phased together. They are at a height of 90 feet. This antenna is also a multibander used thru the tuner. We primarily use this array as a NVIS antenna for short range on 40 and 75 meters due to its very high angle of radiation on 40 and 75 meters.
We will describe how the antennas compare from band to band starting at 160 meters.
1) 160 Meters:
The loop does extremely well out past 200 miles due to its low angle of radiation. It is 2 wavelengths long at 1058 feet, this flattens the high lobes out alot flatter. This was the main reason we started with the loop long at 2000 feet. Because of tuning problems on the upper bands, we had to compromise and shorten the loop to its present length of 1058 feet.
The 160 meter Carolina Windom does better than the loop from 200 miles and closer.
The Co-linear is not operated on 160 meters.
2) 75 Meters:
The loop performs the best at long distance from 300 miles and longer.
The 160 meter Carolina Windom is also good from about 300 miles and past, but it is about 10db down from the loop.
The Co-linear is 10 to 20db stronger in signal than both the above antenna's at close range. This is from 300 miles and closer.
3) 40 Meters:
The loop performs the best at long distance from 400 miles and longer.
The 160 meter Carolina Windom is decent from about 300 miles and past, but it is about 15db down from the loop.
The Co-linear is 10 to 20db stronger in signal than both the above antenna's at close range. This is from 300 miles and closer.
4) 20 Meters:
The loop totaly out-performs the other 2 antenna's at long distance from 600 miles and longer by about 10 to 20db.
The 160 meter Carolina Windom performs well from about 500 miles and past, but it is about 10db down from the loop on the average.
The Co-linear performs fair on this band. This is the band it was desighned for. It has 6 high gain lobes which perform fair, but the Carolina windom and the loop beat it every time. We found out that this antenna has VERY high angles of radiation when used on 40 and 75 meters. That is the reason We built 2 of them and phased them together.
5) 17 Meters:
The loop totally out-performs the other 2 antenna's by about 10 to 20db, hands down.
The 160 meter Carolina Windom is decent, but it is about 10db down from the loop.
The Co-linear is a dog on this band and i don't use it.
6) 15 Meters:
The loop totally out-performs the other 2 antenna's by about 10 to 20db.
The 160 meter Carolina Windom is decent, but it is about 10db down from the loop.
The Co-linear is horrid on this band and we don't use it here iether.
7) 12 Meters:
The loop totally out-performs the other 2 antenna's by about 10 to 20db.
The 160 meter Carolina Windom is decent, but it is about 10db down from the loop.
The Co-linear is useless on this band.
8 ) 10 Meters:
The loop is incredible on this band! The angle of radiation is sooooo looooow, and the capture area is so great, that it will pick up signals that the other 2 antenna's will not even hear. The loop is at 37 wavelengths at 28.5Mc!! Another plus is that the SWR is not over 2.8 from 28Mc to 29.7Mc.
The 160 meter Carolina Windom is decent, but the loop is superior.
The Co-linear is useless on this band.
9) 6 Meters: (YES! 6 Meters)
The loop works exceptionally well on this band. The SWR is not over 2.5 from 50Mc to 54Mc.
The Carolina Windom is flat all the way thru this band and works terrific. No tuner needed.
The Co-linear is useless on this band.
10) 2 Meters:
I have tried the loop on 2 meters with decent local results, so it does radiate. The match is not bad, SWR of not more than 3.0 from 144Mc to 148 Mc.
The Carolina Windom radiates fair (especially off of the ends) on this band, and the match is good.
The Co-linear is useless on this band.
Well that is the performance of the antenna's here in the Swamps of Louisiana.