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Antenna tuner question.

I had a 1:4 match in my mobil. Tried alot of things. Got it down to a 1:3. Went out and bought a MFJ 971 and brought my match down to flat,anywherer I go.$114.00
 
I had a 1:4 match in my mobil. Tried alot of things. Got it down to a 1:3. Went out and bought a MFJ 971 and brought my match down to flat,anywherer I go.$114.00

You haven't changed things except now your transmitter is a bit happier than it was. You still have the mismatch downstream from the tuner - unless you installed the tuner RIGHT at the antenna feedpoint.
 
as stated above
if your antenna hooked straight to your swr meter if it says a 2.5 swr
then you put a tuner inline then play twist the knobs on the tuner then you see a 1.0 swr you got it

then everything from the tuner to the antenna is still a 2.5
 
Well my perspective is a little different from you guys ....I slipseat tractors in my mobile . So, I carry a tuner / matcher in case I have to tune my antenna a little. I drive one tractor to VA. go to bed , drive a different tractor back . One tractor 's antenna might show a 1.5:1 SWR , the next might be 2.0:1 so if it's not good I twist the knobs give my radio an SWR that IT likes & drive back to GA . That way my equipment is still OK to use the next time . Now , If this was a permanent install I WOULD take the time to get those readings down to a reasonable level but, slip-seating it's just not worth the time or effort . Besides , I would hate to spend an hour to get a great SWR go the next terminal & have to get another tractor and start the whole process over again !
 
is always good stuff on threads like this
regardless how much a newbie or not one is

is what makes this site so good
equal learning for all lol
 
It's a lot about convenience.

Is it 'better' to always have things absolutely 'right'? Of course it is. Is it always possible to have things absolutely 'right' in every case? Of course it's not. Unless you only do one thing, never do things differently, or in another place.
Convenience always 'costs' something, no way around that. If that 'cost' isn't excessive, if it doesn't 'cost' more than you can afford, or more often than you can afford, why not?

Convenience doesn't mean the same for everyone. What I might think of as convenient might seem the stupidest thing someone else ever heard of. Is that always 'bad'? Nope. Can it be 'bad'? Sure, depending on how convenient it is to that 'judge', and if that convenience doesn't get totally ridiculous (another subjective opinion!).

Wanna use a tuner? Fine, go for it. Don't want to use one? Fine, don't use one. If I find that using one is 'better' than not using one...for me, I'm going to. If I find a more convenient way of doing things, I'll probably do that too/instead. Am I always right? Why sure! Just ask my banker, doctor, and attorney ;)...
- 'Doc
 
Just for the heck of it, I connected an MFJ 969 tuner up with my FT847 and an Imax 2000. The antenna is resonant on 10 and 11 meters without the tuner. The SWR is also nearly 1 to 1 on 15 meters without the tuner, and only about 1.6 to 1 on 12 meters Then, using the tuner I can get a flat SWR on 17 meters, 20 meters and 40. I haven't tried 80, because it seems silly.

On the air, I do great on 10 and 11 when the band is up. 12 meters I haven't heard anyone yet. 15 meters I seem to be able to get back to anyone that I can hear reasonably well. About the same on 17 meters, I can get in if there isn't a big pileup. 20 meters is touch and go. It is kind of noisy, but I got a couple of decent contacts and a couple of marginal ones. 40 meters I haven't got anybody to come back to me yet, but I can hear quite a few.

So, your mileage may vary, but I am pleasantly surprised at how many contacts I made without much trouble on 15 and 17 today, and, to a lesser extent, 20.

I ordered up a bunch of ladderline and some coax and connecters and stuff, then I am going to get some wire and make a couple of wire antennas and see what I can do. This tuner has a built in 4:1 balun, 2 coax outputs, and a built in dummy load and antenna switch, so I should be able to do some experimenting. I am going to make some insulators out of some pvc conduit I have here. I have a buddy who can climb these big white oaks here, so we will be able to get some wire up in the air in the next couple of weeks, weather permitting.

Anyway, a tuner makes it possible to do alot with an Imax2000.
 
Greetings Highlander!

You'll much more pleased with the results of your wire antennas with the ladder line. Even though the tuner is making your transciever happy, the futher away from resonance the efficiency is going way down. Some of your power is radiating but alot of it is is being lost in the coax as heat. Using the Imax as a multiband has it compromises. If you can put individual wire dipoles resonate for each band that would be great and no tuner would be needed. Unfortunately not eveyone has the space to put up a resonant antenna for every band so tuning a wire of some configuration has its advantages. Of course if it has to be a multiband wire your'e better off feeding it with ladder line. It's alot less lossy and you'll be getting more of your wattage out into radioland. Good luck on putting up the antenna(s).

73's!

Wayne C.
 
Hi Wayne,

Yes, I am psyched about getting some antennas up. We are going to build two "Mystery Antennas" : http://www.w5gi.com/mysteryantenna.htm

and two Off-center fed Dipoles: http://www.w8ji.com/windom_off_center_fed.htm

and compare performance between them. I am going to use my MFJ 969 at my house, and I also bought an MFJ 945E for my friend to use, since he doesn't yet have a tuner, and his funds are a little light right now.

He also hasn't upgraded to general yet, he is going to go take his test later this month. But he's been listening to me making contact after contact on 15 and 17, so he is even more motivated!
 
Well I finally got the W5GI "mystery antenna" up at around 55-60 feet, strung between a tree on one end and a mast on top of my house on the other end. It is approx 103 feet long, and is center fed. I am feeding it with RG-8 coax.

It has <1.9 to 1 SWR on 80, 40, and 20 meters. It is a little higher than 3:1 on the higher bands, but my vertical works well for 17, 15, 12, and 10 meters. The W5GI is working GREAT on 20, 40 and 80. It is a resonant 3 element collinear array at 20 meters, and 100 watts have so far netted me Spain, Italy, Slovenia, Argentina, USVI, BVI, Mexico, Trinidad, and Barbados, as well as several US states and Canadien provinces. And that's with really casual approach, only a few hours tops over the last week or so. I can seemingly get back to anybody I can hear on 40 and 80, and get lots of 59s on those bands as well.

I have it oriented to favor 40/220 degree paths, but it seems to work fine in all directions.

The materials worked out to about 40 dollars per antenna. The most expensive component is the 300 ohm ladderline, which everybody was out of except the wireman.com, and they only had the more expensive .27 per foot stuff in stock.

I am very pleased with the antenna, and highly recommend it. It works really well. When we had it temp mounted at only 25 feet it was a little anemic, but it came alive when it got up above 50 feet.

I am going to build an off center fed dipole that Sonwatcher sent me a link for, and try to set it up to favor a pattern perpendicular to that of the W5GI, and be able to switch between the two.

Then I want to try to make a 2 element 6 meter Quad. I got an old RatShack rotor for free, and it works---should be plenty to turn a small quad.
 
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I think a 'Good For You' is appropriate! I'm going to be interested in how the OCF works out too. As you can probably see from the graphs done on it, it's going to be fairly 'sharp' about where it sees a low SWR, and that tuner will certainly come in handy.
I'd also be interested in what you would see if you duplicate that first antenna and mount it 90 degrees from the first antenna (full 360 coverage).
- 'Doc

The only 'catch' with using 'Mini-8' type coax is that it's sort of voltage/power limiting with SWR present. Doesn't mean it's a bad choice, just that it has limits. (It's that foam dielectric as opposed to a 'solid' type.) Oh well, any 'all band' antenna is a compromise, just depends on where it's most convenient to make that compromise...
 
Doc, I actually have enough materials to make one more W5GI. I might see if another buddy wants to try one at his place.

I'll post how the OCF dipole works out--I'm going to build one that is 137 feet with a feedpoint at 27.4 feet from one end, and feed it with 300 ohm ladderline.

BTW, I had to send a brand new MFJ 969 and a 945E to MJF for warranty repair---both brand new, both defective. It has been over two weeks and they haven't made it back to me yet---not pleased.
 
I don't think I'd be very pleased either. I think it's a fairly common 'test' for MFJ products to pick them up and shake'em, listen for rattles, sort of. Sometimes, that saves a trip back to MFJ. Not exactly the 'bestest' quality control in the world, but still not that bad either, all things considered.
- 'Doc
 
I use a LDC 7000 tuner with my IC7000 connected to a Maco 5/8 tuned for 11 meters and it tunes to 1.2 or lower on 10 meters. That way I can switch from my grant xl to my IC 7000 and use the same antenna. I dont think it is to much loss as I still get good contacts on 10 meter. 11 and 10 are not to far apart but I would not try it on 6 meter or say 12,15,17,20, or so on. I will get another antenna for those.
 

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