Antenna Tuner
- Thread starter billdean
- Start date
ka3jjz
Wiki Admin Emeritus
Well let's start with the misnomer 'antenna tuner'. A TRUE antenna tuner is at the feedpoint of the antenna and uses a shot of RF to tune the radio to the antenna. For example SGC makes some very fine ones but they are mucho expensive.
What you are likely looking for is a transmatch. For what kind of antenna? Coax or ladder line, or both? Frequency range? What are you trying to tune? Be specific here
Mike
What you are likely looking for is a transmatch. For what kind of antenna? Coax or ladder line, or both? Frequency range? What are you trying to tune? Be specific here
Mike
I'll assume the " tuner" in the 710 isn't working enough for you. Please as asked above advise what antenna, which feedline and what bands you're needing to tune.
Right now a wire antenna. Likely all I will use here is a wire antennas and or a vertical one, of one sort or another. I didn't really know at the time I wrote this that tuners were so expensive. I thought a tuner would be easier than monkeying with radials and different Unun heights. I have an DxExtreme 88' end fed antenna that gives me problem especially on 75/80 meters. 5 to 1 is the best I have been able to get. I had it as a sloper at first and it was not good there, so I reset it to I guess a horizontal "L" if there is such a thing. It parallels the ground. Unun at 20' sloping up to 35' at the pulley, and does a left turn sloping down to 30'. I am using LMR-400 coax. Suppose to do all bands HF 160m to 6m. It is really not working all that well as a multi band wire antenna. It's probably a stretch to expect good SWR on 10m and 80m.
OK and again the built in tuner in the 710 isn't working? Unless I'm mistaken you got a FT710 and it should have a built in tuner.
This is relevant due to it may change the recommendation for an external one.
Yes it's working but it only tunes 3 to 1 or less
prcguy
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How much room do you have for a wire antenna? If you have 133ft an 80-10m EFHW or OCFD will give you a good match on all bands 80-10m except for 60m. The shorter 64ft version has a good match on 40/20/15 and 10m. The 3:1 tuner in your radio will take care of any problems and these antennas will radiate a better signal than your non resonant end fed and will not have RF on the coax like you probably have now.
MyAntanna's EFHW-7510-2K-Plus will be here this week. Yup lots of RF coming off that the coax. I have myantennas choke CMC-154-3K 1-54MHz at the radio, as the DxExtreme say not to use one at the unun.
prcguy
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Congratulations on the antenna purchase. The reason they don't want you to use a CMC on a non resonant unun type is because the coax is a radiating part of that antenna. You really need one but place it closer to the radio so you have some hot coax to help it work.
Since you already have the CMC at the radio per your post, I guess it's not possible to move it closer. I'd wait till you see if the other antenna works better and if not, consider either the LDG pro 200 or one of the Mat Tuners if you're not going to run an amplifier. I've had fair luck with the LDG pro 200 with several different types of antennas.
Truthfully I'm going to repair my Yaesu FC-40 tuner which tunes at the wire wire itself and just go back to using that I think here. You'll need to attach a counterpoise to it (I used a ground rod on occasion with some success) but that will help the coax losses tuning it directly at the antenna. The FC-40 is finicky about what length of wires you use on occasion but I used both 65 and about 90 feet of wire at different times and it worked on most the bands. (not 60 meters)
Truthfully I'm going to repair my Yaesu FC-40 tuner which tunes at the wire wire itself and just go back to using that I think here. You'll need to attach a counterpoise to it (I used a ground rod on occasion with some success) but that will help the coax losses tuning it directly at the antenna. The FC-40 is finicky about what length of wires you use on occasion but I used both 65 and about 90 feet of wire at different times and it worked on most the bands. (not 60 meters)
This is likely the best answer to the problem you're having. If you can get that RF of the coax, that will be a great help.
