MFJ 971 vs LDG Z-817

Started by CroPrepper, June 08, 2018, 04:51:04 am

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Hello guys,

I am about to buy my first real antenna tuner. Although I got the QRP Guys Z Match tuner, I wanna have something more powerful for scalability.
I am currently really struggling on what to choose. My favorite is the MFJ 971 tuner. It's small and can be set to QRP use (max 6W) with integrated SWR and power meter. Also it can be used with higher power (for the time after I get an MX P50m amp).
But somehow the autotuner from LDG got into my head, it's smaller and more portable. But it can only do 20W max...
Can someone show me the pro's and con's to each tuner?
I don't wanna waste my money...
I really appreciate any information!



Get the LDG atu for 817, Is the better choice.

I used a lot of tunners with the 817 but the best is the LDG

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Sapere aude


Hi Jon,

thanks for your suggestion. Can you explain what is better on the LDG than the MFJ?


The LDG tuner is a automatic tuner and the MFJ is a manual tuner much like the one you already have. I agree with Jon, buy the LDG or just keep the one you have.



The LDG is pretty big... I like my Elecraft T1 but it is expensive, and when the antenna is tuned, it doesn't matter then if you have an auto or manual tuner, the radio doesn't care! It can however see very high SWRs for short periods from an auto tuner... So better use an SWR bridge with resistors. A good manual tuner like the 4S or ZM-2 does everything you need. The one you have should be sufficient, but of course we never have enough QRP tuners...



June 08, 2018, 01:31:21 pm #5 Last Edit: June 10, 2018, 10:53:02 am by Jon_Garfio
LDG 817 is cheap (compared with Elecraft T1, p.e), is lightweight, fits perfect over the rig.

And for quick tunning, the best way is a auto tunner.

I like and enjoyed so much with Z-Match, transmatch and all manual tunners, but un this case, for 817, primary option Will be the LDG.

I am a big fan of MFJ tunners, I have two models and I ownered about four or five more.

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Sapere aude


It does not matter for me if it's auto or not, turning knobs is fun for me  ;D Somewhere I read that autotuners are not so good for the finals as they are exposed to high SWR during the tuning process. My QRP tuner from QRPguys is okay, but not able to tune my random wire antenna on 80m (~25m long, 71 feet I think). A possible cause is also the environment at my home, a lot of QRM here. Haven't tried to tune it outside in nature yet.
I somehow got the impression that manual tuners are able to tune a wider range of impedance than auto tuners. I can't find any confirmation about that though.
Also, when using an amp in future that is more than 20W, how to use it then (LDG goes to 20W max). I assume the tuner is put between the radio and the amp then and disabled during tuning?

So far I got:

LDG 817 autotuner:
- autotuning
- no hassle
- smaller than MFJ

MFJ 971
- SWR Readings
- Power out readings
- can attach a random wire directly to the tuner if necessary
- supports up to 200W AND Qrp up to 6W
- finals not exposed to high swr during tuning process
- no batteries needed
- manual tuning = you got the control on what is happening


Pretty much...

It's hard to decide. I use both. With the T1, I just press the button and bingo! It will take upwards of 30-40W. It's quick and small... With my ZM-2 or 4S, tuning is safer for the radio's finals, a bit slower, but it works as well, and I don't have to worry about the battery being dead.

All in all, I'd say a small manual tuner with a bridge is better. Of course, we all like to just press a button...



I just bought the Super Antenna MP1DXMAX Dual HF plus 2 meter Bands SuperWhip Tripod All Band Antenna with Clamp Mount and Go Bag through Amazon prime.
My go bag radio is the 817nd with the lg auto tuner, also have the 20 watt goal zero portable solar power system witch includes a converter so I can directly plug in my radio like a wall mount.  Going to put it all together and try it and will post my results.

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