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Joined: Wed, Nov 5th 2014, 18:48 Roles: N/A Moderates: N/A

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Topic Created Posts Views Last Activity
What do I trust, my tuner or my analyzer? Jan 26th 2016, 18:49 7 1,043 on 27/1/16
MFJ-949E Tuner with Comet SBB-5 Nov 6th 2014, 17:28 3 1,655 on 11/11/14

Latest Posts

Topic Author Posted On
What do I trust, my tuner or my analyzer? AF9U on 27/1/16
Ok, that is very helpful Zack. Maybe I'll add a balun and see if my readings are closer between the tuner and the analyzer. I wanted to get a balun anyway. Thank you very much!

Drennen, AF9U
What do I trust, my tuner or my analyzer? AF9U on 27/1/16
Thank you Bill for the reply again. I must apologize for my input/output labeling in my post. I had it connected correctly, I just called it the wrong thing. In fact, on the actual tuner it doesn't say input/output. It says Transmitter and Coax1 or Coax2 depending on which you have selected. But good catch...that probably would have fixed my problem. I'll keep researching, based on your description above I should be seeing about a 1:1 match on the transmitter side coming off the tuner and I am seeing around a 1.8:1. Something isn't right.

73,
Drennen. Af9U

What do I trust, my tuner or my analyzer? AF9U on 26/1/16
Well, I have tuned the antenna for a particular frequency. And that is what I am trying to analyze. I'd like to know if what I am showing on the tuner is confirmed with the analyzer. Wouldn't the output of the tuner (I am referring to the coax that goes from the tuner to the radio) be a different SWR after it's been tuned? Or is it an unreliable SWR because of the tuned? That is what I am trying to understand?

Thanks,
Drennen
What do I trust, my tuner or my analyzer? AF9U on 26/1/16
Hello friends,

Here's the setup: I have a simple homebrew 20 meter dipole up in the attic (no balun). Off the feedpoint, I have 100 ft of RG8X going to the tuner in the basement. There is about 20-30 feet of extra coax than I need, but it's what I had and I figured cutting and putting my own PL-259 on there would have been worse than leaving it long. (If this is a big issue...let me know)

I can tune my SWR to about 1.4:1 around the band. Not much better than that, but I'm not a full half wave off the ground either. So that's a factor. It's up about 26 feet.

My question is. Why does my MFJ-949E give me a 1.4:1 SWR, but if I connect my MFJ-259C to the output of the tuner I am showing about 1.7-1.8:1 on the same frequency? Which should I trust?

Thanks,
Drennen, AF9U
MFJ-949E Tuner with Comet SBB-5 AF9U on 11/11/14
Thank you Bob, I appreciate the information. I thought I had read it would tune almost any antenna, but I obviously misunderstood.

Thank you for clearing this up for me.

Take care,

73,
Drennen

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