New Sirio Tornado 27

[Galaxy 959]

Dallas I edited my post where it shows the messed up reading on the Analyzer. I said it was the old coax. I meant the new coax. It was the new coax I just installed. I took a reading on it before I adjusted the antenna to 41 1/4 like it was suppose to be in the first place.
The SWR was just right at 1.2 with the old coax and about 55 resistance but that was with the antenna at 35" to get it just that good.

 

[The DB]

Doesn't that meter show X anywhere? I'm not seeing it on your pics, and X is what is important. The SWR on the meter is a very distant second in comparison... Seriously, SWR is like the penny next to the X variable which is the equivalent of the $100 bill in comparison...


The DB

 

[Galaxy 959]

Doesn't that meter show X anywhere? I'm not seeing it on your pics, and X is what is important. The SWR on the meter is a very distant second in comparison... Seriously, SWR is like the penny next to the X variable which is the equivalent of the $100 bill in comparison...


The DB

No this is the basic MFJ. I got it gave to me. Its all I have except a inline SWR meter. This MFJ has input and gate on the top of it but I have no idea what it is.

 

[The DB]

Did some research and found a manual for that version. Yep, no reactance. That means the B version of that device was a serious upgrade over the original.


The DB

 

[BBB]

Interesting read on the MFJ 259B and measuring reactance:

http://owenduffy.net/blog/?p=2436

 

[Marconi]

The coax is 2yrs old this month. Its RG8U Foam approximate 50' length give or take a couple feet. I cut the end off to pull it through the floor to remove it. I plan on trying to fix the ends and putting the Antron 99 on my shed. I really don't know what your asking about the <2.00:1 SWR bandwidth?

That's OK 959, I was thinking maybe you could check and possibly figure out why your feed line was acting as you indicated.

The bandwidth I asked about is a SWR measurement for the antenna...read from where the SWR is less than <2.00:1, at frequency points both higher and lower in frequency than your center frequency.

You do this by attaching the meter to the feed point or the radio end of the feed line, whichever is conenvient. Then you scan the frequencies both up and down around you best SWR until you see an SWR of 2.00:1. You record both the high and low frequencies and subtract the two. The difference is the bandwidth.

Your Tornado 27 spec sheet shows us the bandwidth should be about 1300 khz, and this is 1.30 mhz.

Why is this important? This is just another check to see how close your installation comes to the antenna specs.

There is also a simple way to check your feed line. When you get the connectors re-attached, let me know and we can discuss this simple checking procedure.

I record this information on all of my feed lines starting when new. This check also allows me to keep an eye on the condition of the coax I use.

Does any of this mater as to performance...probably not, but it is something to know and understand about antennas, installations, and feed lines.

Good luck and keep us posted on how this one compares with your A99.

 

[Galaxy 959]

Maybe someday I can upgrade.

That's OK 959, I was thinking maybe you could check and possibly figure out why your feed line was acting as you indicated.

The bandwidth I asked about is a SWR measurement for the antenna...read from where the SWR is less than <2.00:1, at frequency points both higher and lower in frequency than your center frequency.

You do this by attaching the meter to the feed point or the radio end of the feed line, whichever is conenvient. Then you scan the frequencies both up and down around you best SWR until you see an SWR of 2.00:1. You record both the high and low frequencies and subtract the two. The difference is the bandwidth.

Your Tornado 27 spec sheet shows us the bandwidth should be about 1300 khz, and this is 1.30 mhz.

Why is this important? This is just another check to see how close your installation comes to the antenna specs.

There is also a simple way to check your feed line. When you get the connectors re-attached, let me know and we can discuss this simple checking procedure.

I record this information on all of my feed lines starting when new. This check also allows me to keep an eye on the condition of the coax I use.

Does any of this mater as to performance...probably not, but it is something to know and understand about antennas, installations, and feed lines.

Good luck and keep us posted on how this one compares with your A99.

If this is what your asking which I think it is. Its 26.687-27.510=823

 

[Marconi]

If this is what your asking which I think it is. Its 26.687-27.510=823

That's it 959, it = 0.823 mhz and that is very close to what my model shows.

 

[Galaxy 959]

That's it 959, it = 0.823 mhz and that is very close to what my model shows.

So Marconi what height would be best for me to put this antenna up? Up to 40' is my options. I have it right at 26' right now. For talking local and skip.

 

[222DBFL]

The higher the better. Get it at 40ft if that is what your limit is. JMHO. Should work well at that height.

 

[Marconi]

So Marconi what height would be best for me to put this antenna up? Up to 40' is my options. I have it right at 26' right now. For talking local and skip.

I see 40' feet is better.

The models below show there is a gain advantage of a little over .50 dbi in gain at 40' feet which is not much, but there is a nice drop in the maximum radiated angle of 2* degrees between at 40' feet compared to 26' feet, and that is good too.

I don't know if you will be able to tell the difference, but higher is better up to the point you don't feel safe about you install.

Good luck and be safe.

Thanks again for you help, and keep us posted.

 

[M0GVZ]

The SWR was just right at 1.2 with the old coax and about 55 resistance but that was with the antenna at 35" to get it just that good.

If you are taking the measurements at the radio end of a length of coax then any impedance and reactance values are meaningless due to the effects of the coax. They're only of value at or as close to the antenna socket as possible.

 

[Galaxy 959]

Well I got it done today guys. Its been a while but finally complete other than grounding. 40' to the bottom of the Sirio Tornado 27. SWR is flat across 11 meter band. Just over 62' of Times Microwave LMR400 coax. Haven't had a chance to talk on it as I just got it done.

 

[Needle Bender]

That's BEE YOU TEE FULL!
Maybe just a touch long on the coax, unless you want it to dial in around 26.900. For center of band 2 WL = 61' 6" - but DANG CLOSE!

 

[Galaxy 959]

That's BEE YOU TEE FULL!
Maybe just a touch long on the coax, unless you want it to dial in around 26.900. For center of band 2 WL = 61' 6" - but DANG CLOSE!

Actually Needle Bender I think that's exactly what my coax is. I put just over 62' but that's wrong. I ordered 62' and the guy trimmed it and put the ends on it then sent it to me. Thanks for the compliment it was a lot of work getting this done.