I have been thinking about building a new antenna, and decided that I want to run a double zepp through the balun built into my MFJ -949. This video has me now convinced that I want to do this because it took the "sorcery" away from how the tuner operates.
9:00 this explains something I've observed with my 949E, thank you for that simple explanation. I was looking for a video like this before but family life and job life took me away from research... Matt not be the same model I picked up (the 949E has a dual-needle meter) but it's obviously the same basic design...
I just bought a used yaesu ft-817nd and an ldg auto tuner. I also found the CQHAM TB-BOX. It's a manual tuner and power bank built together to fit the 817. Honestly I am more excited about how the TB-BOX integrates with the radio than I am about the LTG. I am also interested in the simplicity of the manual tuner hence the reason I looked up your video. Great video explaining everything and showing exactly how it works. Thank you.
thanks for the review, I have and use the MFJ-949E, no auto-tuner here, it has served me well, only slight disadvantage to a tuner like this is that you require an SWR meter in between it and the radio, I do like the built-in SWR meter, al ve3gam
I have a MFJ-901B and it works great for a 100 watts or less. Uses it many times for qrp. As stated in the video don't hot switch it while transmitting.
I have an 901 Versa tuner that is a tan and wood grain in color. I wish it had a date one it but I actually have it on my rig right now and it’s a jam up tuner. I hope to get another for my /p rig.
Good video! I have trouble hearing you sometimes. I have a MFJ-949E. It has a power meter, SWR meter, Dummy Load, and antenna switch Plus everything in that tuner.
Awesome video and explanation! I have a Versa Tuner II (MFJ-941E) that I feel the need to connect to my Nano VNA and...play around! Be well and stay safe Ape.
Great video. It's cool seeing the changes occur, as you make the adjustments in the tuner. It also gives you an appreciation for how complex tuning adjustments can be.
I see your tuner has the flaking paint on the bottom front too. If MFJ reads this, fix that part of the manufacturing process. I had paint chips falling onto my radio display.
Oh ok so that makes sense. If the tuner can cover my range of mismatch use the tuner otherwise use a dedicated transformer. On that note if I might add that a tuner won't act as a choke for CMC (unless there is a built in balun) and a transformer could help to lower the impedance mismatch enough to allow the tuner to do the rest ( if a tuner is still needed....). Tell me if I'm wrong and thank you for the awesome content
@@TheSmokinApe Ok I just got my cable in from HRO. Question How does it plug into the radio and tuner ? I got no instructions ? The molex (white) power plug the barrel power plug and audio jack. I could not find a youtube video on this subject. I would apreciate your help. Say I got it figured out. This is cool. When you turn the radio on. Then turn the tuner on. You set the power for ten watts. go to AM mode. Choose your HF frequency and the radio and tuner does the tuning automatically.
I good video many compliments, i should i buy a manual tuner for my 20 watt max hf radio. I am undecided between the MFJ 901 model and the MFJ 902 model. The 901 tunes up to 160m (1.8) Mhz while the 902 has 6 Meters (which I don't care about) but starts from 80 m ie 3.6 Mhz. The 901 has the coil in the air, the 902 has coils wound in 3 toroids. What's the difference? Which do you recommend to buy between 901 and 902? I am inclined to buy the 901. Could you tell me how to make the bridge? I saw in a forum that they mount a switch which is certainly an alternative to the jumper. But what specifically is the jumper switch for?
@@TheSmokinApetahns for your respons. I would like to know what is the jumper that is made between the wire connector and the coaxial. You talk about it in the video when you describe the connectors of the balanced line and the wire connector
Great video, Ape. This is a superb didactic illustration of the role, function and use of a tuner --the ATU merely being a machine-driven optimized version--in an antenna system!
Finally was able to be left alone long enough to finish watching I never understood how to plot smith charts manually or how to make the calculations but clearly there's no magic to them and they shouldn't drive people batty. I just need to take the time to learn them, but I would like to see how the different adjustments affect that chart specifically. If I ever pick up a nano I'll be able to do that for myself. This is a good primer on what these tuners do, though. Question: is my understanding correct? Tuning the antenna with a tuner only makes the antenna "look better" to the transmitter. Correct or incorrect? I mean, a ten foot long wire isn't actually made resonant itself, so how can it send radio waves out any better? I think it doesn't. Does the tuner just re-reflect the reflected power back to the antenna? I wonder if that can affect radiation pattern any at all. Anyway, thank you for this informative video!
This unit did not work for me. Running an indoor loop antenna, my rig's max 3:1 ratio internal tuner handled all bands from 80 to 10 with tuned SWR well below 1.5:1. Placed a MFJ-1026 noise canceller in-line to kill a QRM problem, but this MFJ unit doesn't allow the use of the rig internal tuner without frying the noise canceller, forcing me to use an external tuner. Tried the 901B over the course of a few months, and despite it's reputation for being able to tune up a wet noodle, it killed my power out across all bands, and the SWR never went below 2.5:1. Tried a wide variety of tuner settings and different coax jumpers at various lengths - newly purchased LMR-400 - to see if that voodoo would help to no avail. Needless to say, my 901B is up for sale 😑
That looks alot like my MFJ-949e inside. It's simple and works great. Thanks for the detailed review, you explained things much better than the instructions.
I like your style! Going down to the nitty gritty! I wish you could go more into the Smith Chart but I understand that it is audience dependent! So you have tuned your antenna on both the Smith and SWR views in NanoSaver? What happens if you connect the Antenna line on the S21 port? Is that even applicable thinking that you can tune the entire system with the antenna inline??
noob question that I’ve been afraid to ask. If I place an antenna tuner on an end fed random wire, should the 9:1 unun be at the feed point as usual? Or does the antenna tuner replace it? You said a 4:1 unun is part of the antenna tuner, does this obliviate the need for the 9:1 unun?
The tuners should be at the radio output and the 9:1 at the antenna feedpoint. The 4:1 in the tuner is used for connecting antennas fed with twinline and not coax.
Is it true that an antenna tuners only benefit is to protect your radio from reflected power, and that they can't actually improve the strength of the signal radiated by an antenna?
Kinda. When you use a tuner at the coax feed point you are matching the radio to the antenna system, transmission line and antenna. When your signal hits the antenna you still have the mismatch between the coax and antenna which will reflect back down the transmission line. You will get loss, due to the coax with each reflection, the reflections persist until the power is used or lost.
@@TheSmokinApe Thanks for the reply, that makes sense, I think. But what if you could place the tuner directly at the antenna, so that the output from it didn't go through the impedance mismatched coax? It seems like then, by impedance matching to the antenna, you could avoid much reflection and actually get more radiated signal. I haven't found anyone who has actually tested this though!
@@smith0426 they actually do put remote tuners at the antenna for this reason, obviously it’s a more complex configuration. Also, folks will build passive matching networks for mounting at the antenna. Most hams however choose to match / tune in the shack which is easier.
Really enjoyable, Ape! You are having too much fun! Are you an electrical engineer? Is there an Ape bio or resumé laying around somewhere? Your videos are really, really good! Thanks and ATB! 73, John - KK7JBZ
Nicely explained and great use of the nanoVNA. I have a Heathkit SA-2060A manual antenna tuner that I built way back in the 80’s. It’s way bigger (it will handle 2KW) but its internal circuitry is very similar except that it has a roller inductor. I haven’t used it since the 1990s and I can’t wait to hook it up to the NanoVNA and get it back online!
Who needs a tuner? I had kenwood 520se and swr meter and nothing else and vertical gp antenas and many dxes worked with it. Cut the antena wright and swr 1:1,1 or so.
