Antenna Tuners

[pkveazey]

I'm glad to see a lot more activity on the forum about emergency Medicine and HF Radio Communication. There has been brief mention of antenna tuners. Building a Manual antenna tuner is a piece of cake because it only requires a tunable coil and a tunable capacitor in a box and has to be able to handle the power applied to it. If you use a manual tuner, you are definitely going to need an SWR/POWER meter so you'll know when its tuned to perfection. NOW, on to auto-tuners. I have two IC 718's that don't have auto-tuners built in but they do have a button for use with an auto-tuner. I bought and mounted LDG auto-tuners to the top of both my IC-718's. They are powered by the radio and they don't have to be operated independently of the radio since I have the auto-tuner button already built into the radio. Now I'm going to get into something controversial. The myth that Antenna tuners don't do anything to improve receive or transmit capabilities because all they do is make the radio happy with a proper antenna match. Well, that's sort of correct. If you are transmitting or listening through a non-resonant antenna and you dial in an antenna tuner, the received signal actually gets better. Hmmmm…… That can't happen. Oh, yes it can. OK, but it doesn't do anything for the transmitted signal. Oh, yes it does. If you transmit into or listen on a non-resonant antenna then you have a bad match and that equals a non-resonant circuit. As soon as you dial in a proper match using an antenna tuner, you still have a non-resonant antenna but you now have a resonant circuit. That's why your radio now works better with the tuner than without. Not to mention that the radio is a Hell of lot happier being connected to a resonant circuit. I cut my wire antennas to create as good a match as I can at the most used frequencies. Then, just before I get on the air, I hit the auto-tune button and nail down the exact match. I'll try my best to be on the air at 3.967 Mhz at 5PM. Sometimes I forget or get busy with other matters and I miss out.

[JohnyMac]

I hope you make it PK!

I just did a recheck on propagation for Sunday and from N.FL on up the coast to the Canadian border it looks like TX and RXing on 80-meters ranges from 87% in N.FL to 100% in Watertown, NY operating from my QTH in NE PA.

[Romeo Foxtrot]

I agree, tuners are great, especially for random length, multi band wire antennas...

That's what i am running now, 153ft end fed, nvis config, strung thru trees at 20' up, into my ldg z-100+ to my 100w alinco, i can hit the bands, tune the band, the tuner remembers the tune, so i don't have to re tune each time, just fire up rig, dial in freq and away i go.

Now, being the anal retentive guy i am, i usually do tune up before just to make sure i know...

they also act is an arrestor of sorts to help prevent damage to rig from hi rf, etc.

[NCislander]

Great "Comms" reads all around.  Especially on the Antenna parts.

Thanks...

[Gorlo]

Yep, I always re-tune before I use any HF band. I have a 130' end fed that I use with an Icom 746Pro. An older rig I picked up used, but it has a built in antenna tuner. I usually turn down power to a couple watts then hit the tune button, works great. I also have a FT-857D that I used exclusively for digital modes with an LDG Z-100+ tuner. I had a station in Mississippi running NC for the WRSA Covid watch net thinking I was putting out "extra power" because my signal was strong and I'm in NY. Nope, I was running barefoot around 90 watts. Tuning helps a lot.

[Mustang0268]

Tuning is good...

I tried to monitor the GA net on 3.971, but band conditions to the West Coast are poor to non-existent.  Most likely the "pelosi layer" is interfering..

Mustang0268 sends

[LDG]

pkveazey, I experienced the same conditions that you mentioned. Let me explain.

I also use an IC 718 with the LDG tuner. My rx also increases sharply when I activate the tuner. Why? I don't know.

I also use an end fed 135' antenna, a vertical A99 and a multi-band dipole. The dipole apex is 30', it is 100' long, the ends are at 20'. When I lower the center to 10' my NVIS works quite well. A man down the road from me can hear me perfect with the center at 10' and cannot hear me at all when the apex is 30'. He is about 20 miles away and I live in hill country, therefore, no ground wave.

The primary problem with NVIS is that most people see no need for it. Most folks are shooting for DX, and that's wonderful. Most DX operators see no need for NVIS. Some will even tell you that it's impossible, but it's still being used today by the military, even though we know it's impossible.

Thank you for your comments on antenna tuners. Just thought that I would share my experience and maybe others will try it, too.

73

[NCislander]

Thumbs Up  reading the different setups and your results with them.
73s...