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Sirio 3 ele yagi
- Thread starter SMILEX2692002
- Start date
Thanks for the explanation.
I miss interpreted what you posted as saying DO NOT change dimensions.
Made me think HENRY of all members has so much in depth knowledge of yagis but you said DO NOT change element lengths.
Agreed there is more to the yagi than just changing lengths to squeeze every bit of DB gain and rejection.
But isn't a yagi a compromise antenna anyway? Will 1DB of gain actually be heard on the receive end? Maybe it will, have to be one heck of a good receiver to hear 1db of difference in a signal.
I miss interpreted what you posted as saying DO NOT change dimensions.
Made me think HENRY of all members has so much in depth knowledge of yagis but you said DO NOT change element lengths.
Agreed there is more to the yagi than just changing lengths to squeeze every bit of DB gain and rejection.
But isn't a yagi a compromise antenna anyway? Will 1DB of gain actually be heard on the receive end? Maybe it will, have to be one heck of a good receiver to hear 1db of difference in a signal.
Yes, indeed.
From every text book about beams you will find out that the author says;
A beam is a compromise between gain/front to back/ front to rear/ and swr bandwidth (impedance)
But, say were only interested in a beam that works from 27 to 27.6 Mhz
Then from the user his point of view the 600 khz isnt a "compromise".
Now, if we "sacrifice" in one aspects we can optimize the rest..
So, if we can have for a certain boomlength the best gain / front to rear (far more important than front to back) for that yagi with the SWR bandwidth we agreed on
We have a winner !
The data provided for that 4el in that other topic dus just that.
And thats the "game" producing maximum on all aspects without futher compromising anything.
A fun game as from time to time we all seem to be squeez a bit more out of the antenna.
Kind regards,
H>
From every text book about beams you will find out that the author says;
A beam is a compromise between gain/front to back/ front to rear/ and swr bandwidth (impedance)
But, say were only interested in a beam that works from 27 to 27.6 Mhz
Then from the user his point of view the 600 khz isnt a "compromise".
Now, if we "sacrifice" in one aspects we can optimize the rest..
So, if we can have for a certain boomlength the best gain / front to rear (far more important than front to back) for that yagi with the SWR bandwidth we agreed on
We have a winner !
The data provided for that 4el in that other topic dus just that.
And thats the "game" producing maximum on all aspects without futher compromising anything.
A fun game as from time to time we all seem to be squeez a bit more out of the antenna.
Kind regards,
H>
Bought the Sirio 3 ele yagi today.
Based on my previous Sirio antenna the D27 dipole. I found the D27 dipole to hold up very well over this past winter.
I took it down from the tower yesterday and it still looks brand new.
I also will built the Sirio 3 ele as it was intended. Maybe I could still get 10 meters on it with a antenna tuner?
I look forward to building the antenna and getting it up in the air. I also decided to mount my Imax 2000 above the 3 ele Sirio vs using the D27 dipole mounted vertical off the side of my tower. The Imax 2k works well so until it breaks or wears out I might as well keep using it.
I have coax, but I still need about 55ft of 8 wire rotor cable to connect to my Ham 3 rotor.
Any ideas on who has the best price on rotor cable?
Or anyone have any around there not using?
Based on my previous Sirio antenna the D27 dipole. I found the D27 dipole to hold up very well over this past winter.
I took it down from the tower yesterday and it still looks brand new.
I also will built the Sirio 3 ele as it was intended. Maybe I could still get 10 meters on it with a antenna tuner?
I look forward to building the antenna and getting it up in the air. I also decided to mount my Imax 2000 above the 3 ele Sirio vs using the D27 dipole mounted vertical off the side of my tower. The Imax 2k works well so until it breaks or wears out I might as well keep using it.
I have coax, but I still need about 55ft of 8 wire rotor cable to connect to my Ham 3 rotor.
Any ideas on who has the best price on rotor cable?
Or anyone have any around there not using?
Assembled my Sirio 3 ele beam today. It was pretty easy work. I mounted it on a 5ft pole in my backyard to set the gamma match. That was really easy.
I talked to the east coast right away. Then I tried it on 10 meters and got a station in Minnesota when I pointed it north west. The swr on 10 was 2.0 around 28.450.
I also checked my swr on 12 meters and it was around 2.5.
I will be using it mainly as a Cb antenna. My rig has a auto antenna tuner so it may be fun to try it out on 10 and 12 meters.
My next step is to get it on my tower. I may mount my Imax 2000 above it.
I bought a nice rotor plate to mount my Ham 3 on inside my tower.
The only problem I have so far is the coax cable. I only have Lmr 400 on hand.
I'm worried it will not hold up on either antenna due to the rotating mast.
My friend has some Lmr 240 he would sell me. It has quite a bit more flexibility with added DB loss. Probably not enough DB loss that the station on the receiving end could even notice.
I'm considering changing to the Lmr 240 but would rather use what I have. I don't really want to add barrel connectors to connect a more flexible coax to go around the rotor and connect to the antennas either.
I have to admit that the Lmr 400 is likely overkill for the wattage I run (Never more than 100 watts Pep) and being below 30 MHz. If I go with the Lmr 240 I would sell my Lmr 400.
I talked to the east coast right away. Then I tried it on 10 meters and got a station in Minnesota when I pointed it north west. The swr on 10 was 2.0 around 28.450.
I also checked my swr on 12 meters and it was around 2.5.
I will be using it mainly as a Cb antenna. My rig has a auto antenna tuner so it may be fun to try it out on 10 and 12 meters.
My next step is to get it on my tower. I may mount my Imax 2000 above it.
I bought a nice rotor plate to mount my Ham 3 on inside my tower.
The only problem I have so far is the coax cable. I only have Lmr 400 on hand.
I'm worried it will not hold up on either antenna due to the rotating mast.
My friend has some Lmr 240 he would sell me. It has quite a bit more flexibility with added DB loss. Probably not enough DB loss that the station on the receiving end could even notice.
I'm considering changing to the Lmr 240 but would rather use what I have. I don't really want to add barrel connectors to connect a more flexible coax to go around the rotor and connect to the antennas either.
I have to admit that the Lmr 400 is likely overkill for the wattage I run (Never more than 100 watts Pep) and being below 30 MHz. If I go with the Lmr 240 I would sell my Lmr 400.
Maybe a half wave of flexible coax at the antenna would help. Just saying
P.S. I've never used the big coax but on my tower I'm using RG8x and RG59/u. I use a flexible standoff to hold the coax out from the mast. I also set the coax to where when the antenna is turned fully on the direction that would wrap the coax around the mast,I leave enough slackness so that the coax won't stretch or get damaged.
P.S. I've never used the big coax but on my tower I'm using RG8x and RG59/u. I use a flexible standoff to hold the coax out from the mast. I also set the coax to where when the antenna is turned fully on the direction that would wrap the coax around the mast,I leave enough slackness so that the coax won't stretch or get damaged.
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Got the Sirio SY27-3 beam assembled and set the gamma match.
I pounded a 6ft pole in the ground and mounted the beam on it.
The beam was 3ft off the ground. I made a few skip contacts also.
The swr is close 1.0 on CB 1-40.
The gamma match did take some adjusting. The specs in the instruction manual didn't work for me.
I would hope when the antenna is up on the tower the Swr will stay the same. It would be a big hassle if I had to adjust the gamma match again with the antenna up in the air.
The pictures I posted are for show. The rotor will be mounted near the top of my tower.
If I understand correctly. I have to turn the rotor to the North position on my directional control box and then mount the beam so the director element is facing North.
Please correct if wrong.
I also will be using my Imax 2000 above the beam. How close to the boom of the beam should I attach the Imax 2000?
I have heard some say to get it as close as possible and others say a few feet away. I don't use the Imax 2000 ground plane kit either.
I pounded a 6ft pole in the ground and mounted the beam on it.
The beam was 3ft off the ground. I made a few skip contacts also.
The swr is close 1.0 on CB 1-40.
The gamma match did take some adjusting. The specs in the instruction manual didn't work for me.
I would hope when the antenna is up on the tower the Swr will stay the same. It would be a big hassle if I had to adjust the gamma match again with the antenna up in the air.
The pictures I posted are for show. The rotor will be mounted near the top of my tower.
If I understand correctly. I have to turn the rotor to the North position on my directional control box and then mount the beam so the director element is facing North.
Please correct if wrong.
I also will be using my Imax 2000 above the beam. How close to the boom of the beam should I attach the Imax 2000?
I have heard some say to get it as close as possible and others say a few feet away. I don't use the Imax 2000 ground plane kit either.
Just make sure it's true north and not magnetic north. Two different locations.
https://www.google.com/search?q=mag...=UTF-8&oe=UTF-8&hl=en&client=safari#itp=open0
Just a thought
https://www.google.com/search?q=mag...=UTF-8&oe=UTF-8&hl=en&client=safari#itp=open0
Just a thought
You can put it on your temporary post and point it straight up into the air and recheck SWR. If you have some high trees, you can fabricate a rope rigging and hoist it well above the ground and check SWR that way as well.
I bet you'll like it. I had a Cushcraft TEN 3 that I ran flatside. It was a big improvement over my Ringo at the time.
I bet you'll like it. I had a Cushcraft TEN 3 that I ran flatside. It was a big improvement over my Ringo at the time.
