An old tuner for the new 705

I agree with you! Thanks for the review. It was very helpful to me! Don't let the trolls get you down. What does ammo have to do with ham radio, anyway?

 

Guess you don't operate much from the wilds, eh?

Oh, wait! I see your QRZ page is written in third person. Allow me to rephrase that question...

Guess Guy doesn't operate much from the wilds, eh?

And other question: How did Guy get that particular call sign. Judging from Guy's QRZ page, he doesn't appear to be a closet Juggalo ... but one never knows. Whoop, whoop?

Oh, what! I see now it's in honor of Guy's deceased Elmer, so never mind.

Wonder if Wilson James was a Juggalo? Please ask Guy if he knows.

 

It appears that you are calling an EFHW a balanced antenna, if so, that is incorrect. By definition, any "end-fed" antenna is unbalanced, regardless if it is a half-wave or some other length. There MUST BE an "other half" of such an antenna, you cannot force current into a single terminal, there has to be a return path (such as an RF counterpoise) for an equal amount of current. My comment is intended to be constructive, so that we don't promote false information.

 

I have the antennas4less HF-319 mag loop. For the price, it is great fun! I also bought one for my handicapped brother who lives in an assisted living apartment. He uses it from the top floor of his apartment with a 5 watt cw rig. If I was operating outdoors, I think I would go with a Par End Fed end fed wire that covers 40, 20 and 10 with low SWR. No need for a tuner. PS: I also own a T-1 and the IT-100pro tuner. Use the IT-100pro with the interface cable in my shack with the IC-705.

 

Sure thing. - This isn't a portable antenna at all. Its 50m on each side and has 65ft of ladder line. A doublet is not a resonant antenna, but many hams say they are amazing. In reality, you should cut the antenna pretty close to the band of interest - for a 40m doublet, you'd want 10m of wire on each side. You'd feed it with "any length" of ladder line (that isn't resonant on its own, or any harmonics of the band you're interested in), then you'd use a tuner to touch it up.

My build video on this antenna is here:

 

The misinformation in this video is astounding and a disservice to newcomers.

At 3:34 you refer to "fold backs." Then at 14:11 it's a "strain relief." Please get with the program and use the proper terminology: they're thimbles - or wire rope thimbles.

At 19:07 you say "...it's what's called a pi-network..." That's patently WRONG - the MFJ-949E is NOT a pi-network tuner! It's a T-network tuner.

Far too much time was wasted unboxing/unpackaging. You mentioned "Today's knife to get this thing open is..." is unnecessary fluff and a not-so-subtle product endorsement for Morakniv.

Suggestion: Next time open up the packaging and lay the parts out on the table ahead of time instead of boring and otherwise wasting viewers' time. I believe it's safe to assume that even noobs know how to open boxes and plastic bags...

 

I've toted an Elecraft KX2 and KX3 all over this planet with various home brew resonant 40-10m end fed antennas and now have an Icom IC-705 which I adore. The Elecraft rigs had really good built in tuners to take care of any problems and to also allow any metal of opportunity to be loaded up as an antenna. Just like the OP here, I also purchased an Elecraft T1 tuner as the 705 does not have any tuner and there will be times when a resonant antenna is not available.

When I read some of the ridiculous comments here about only using resonant tuned antennas, especially those posts that start with 'You should", I think to myself, "you should not post" if that's how you're going to introduce your suggestions. Who are you to say "you should'? Your not my momma and I doubt you can cook like her, so why bark at us like that???

Thank you to KM9G for introducing some folks to the wonderful little Elecraft tuner. Its the cheapest thing in its category and I believe it works better than anything else offered for super lightweight QRP use. For those that say it costs too much, fine, don't buy one but don't cry about it when others do.

 

It is a funny comment, since the first sentence above the video literally says: You Must Always Use This Very Tuner. Bad behavior began by this claptrap. Also, misinformation should not be spread. Mistakes can be corrected easily in a video in several ways, but I'm almost sure it will never happen, it is not used to.

 

And in addition to that: an EFHW is already HW, so what's there to tune?

 

An EFHW is half of an antenna. It does not have a 50 ohm impedance. If we assume that the "other half" is also an electrical half wavelength long, we have a full wavelength load which has a feedpoint impedance of around a few thousand ohms. I think that it would need "tuning" in order to present a resonable match to a 50 ohm rig.

 

Many companies make a resonant end fed half wave antenna using a broad band 49:1 to 64:1 transformer that matches the roughly 2.500 to 3.200 ohm impedance. Being a half wavelength long at its lowest design frequency and operating as multiple half waves on harmonic bands makes it a complete antenna. The VSWR across its resonant bands is very good and works fine without an external tuner. Don't confuse the EFHW with 9:1 transformer types using various lengths of non resonant wire, the EFHW blows those away in performance. Lots of companies make EFHWs but MyAntenns makes the best I have seen and used. They have probably sold tens of thousands of them and they work great.

I've also built dozens of 40-10m and 80-10m EFHW antennas and they work about the same as a resonant center fed of the same size, but unlike a coax fed center fed, the EFHW works all harmonic bands with a great match. This is the type of antenna I would normally use with my IC-705 in the field but I will still take my Elecraft T1 tuner to allow experimenting with other antennas.

 

The number of companies that make and market a product, the number of people who believe that those products "work great", and the number of people who believe the large amount of misinformation that is distributed, does not make those claims and assumptions true. There is only science. Science tells us how things work.

Regardless if you use an antenna tuner, or a ridiculous 49:1 or 64:1 transformer, an EFHW (or any end-fed) is STILL half of an antenna. This has been covered many times before, but the misinformation keeps getting repeated and promoted, sometimes for financial gain.

The link to the "End fed half wave" article doesn't seem to work, but here's the source for the text that I copied below: https://w8ji.com/end-fed_vertical_j-pole_and_horizontal_zepp.htm
The following is the work of, and is copyrighted by, Tom Rauch, W8JI:

Can we end-feed a halfwave antenna, or end-feed any antenna, without a ground or counterpoise?
The answer depends on what we want to call a "ground". This simple rule applies to all end-fed antennas, and this rule cannot be broken. The rule is:
Current flowing into the antenna's end must be equaled, at that end point, by the same amount of current flowing into a ground or counterpoise of some type.
An end-fed antenna must have something attached to the feedpoint that carries the same common-mode current away from the feedpoint as current flowing out onto the antenna! The counterpoise can be accidental and not physically obvious, such as the outside of a coaxial cable's shield, parallel currents on a balanced feed line, or currents on a mast or metallic support. This is true no matter how many series traps, isolating devices or systems, or common mode suppression devices, installed at the feedpoint. This current would be called common mode current, and it always causes close-in, and sometimes even distant, radiation.
The counterpoise could also be currents flowing on an intentionally installed radial or counterpoise system, but even an intentional counterpoise results in currents dividing between the intentional counterpoise and accidental paths, like the feed line. Currents divide by how "easy" each path is, or the impedances of the various paths, at the antenna feedpoint. Without a reasonably-sized feedpoint counterpoise, even if we add common-mode chokes at the feedpoint, or use an isolating transformer or network at the feedpoint, voltage across the isolating device increases until the same end-current flows. Even without a direct electrical connection, displacement currents through stray capacitances will cause the same common mode current to flow on the feeder, or perhaps into another unwanted path, at the antenna feedpoint!

 

Hold on one sec... What we cant have a dissenting opinion? if you read back what I wrote my dissenting opinion was not snarky and it was factual. In all actuality I gave an opinion that would save many people money that they may not have to spend. Not all of us can run out and buy a new HF rig and a new tuner anytime we want.

(for the record I do own auto tuners.)

 

I use a Buddipole for my IC-705... pretty damn dead on; so says my Bird 43. Same for my 9:1 balun and forty foot piece of wire.