Kg3v Ham Radio Blog

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Using External Antenna Tuners with the IC-7300

Posted: 06 Jul 2018 07:03 PM PDT
https://kg3v.com/2018/07/06/using-ex...h-the-ic-7300/


I have been trying a couple external Tuners with my IC-7300 transceiver,
with mixed results. They actually both worked, but operation is a little
confusing. The tuners I have tried so far a

Elecraft KAT-500
LDG Electronics IT-100


The Elecraft Tuner is made for the K3-line but Elecraft has also made sure
that it can be used with other Rigs. The LDG IT-100 is specifically made to
be compatible with ICOM radios that use the standard 4-pin antenna tuner
interface. This is a great interface, allowing flexibility to use a tuner
with many Icom rigs. I do HATE the 4-pin connector that connects to the
radio. It is a friction-mounted connector (no keys or tabs to press), but
it is extremely hard to remove. Every time I remove it, I am afraid I am
going to damage the radio. if you have to remove it from the rear of a
radio that is on your desk, reaching over the back of the radio, good luck!

Every time we discuss external tuners on reflectors, a few people have to
jump in and say that you need to have resonant antennas, so why would you
ever used an external tuner, when the IC-7300 has a built-in tuner. The
internal tuners in Icom radios will usually only match an SWR mismatch of
3:1. This is unfortunate, as Elecraft has had built-in tuners that handle
10:1 SWR mismatch for years. I had one in my K2. If you just need a slight
tweak of your antenna to cover entire HF Bands, you may not need an
external tuner at all. For the rest of us, external tuners allow us to
greatly expand the Bands and Modes we can use with compromise antennas.
Elecraft KPA-100 Tuner

This is a great tuner, although not inexpensive. It is built to handle 500
watts, as a companion to the Elecraft KPA-500 500W HF Linear Amplifier. It
has 3 antenna ports. It does a great job of tuning and, like most automatic
antenna tuners, it is very LOUD when it has to search for a match. If you
go to a previously-used frequency, tuning is very quick and you barely
notice the noise.

I do not use the power from my IC-7300 to power this tuner. The maximum
current needed by the KAT-500 is close to the 1 Amp maximum current that
the Icom rigs normally supply on the antenna tuner port. So I suggest using
your separate station power supply for ht tuner. I just connect the data
plug on the Antenna tuner cable to the radio, then connect the separate
power connector to my main supply.

The interface is a little quirky. It seems that pressing the TUNE button on
the rig can do different things under different situations. One thing I
quickly discovered is that you need to TURN ON power to the Tuner before
you power-u[ the Rig. Then pressing the TUNE button on the IC-7300 seems to
tune the KAT-500. You can also press the TUNE button on the KAT-500 to tune
the antenna matching network. If you turn on the IC-7300 before the tuner,
pressing the TUNE button on the IC-7300 attempts to tune the internal tuner.
LDG Electronics IT-100 Tuner

This LDG Tuner is a perfect match for the IC-7300. If you do not need the
flexibility of the KAT-500 or the increased power handling capability, this
is what I would recommend. It comes with the cable you need to connect it
to the Radio. So it is really just plug-and-play. Since it is powered by
the IC-7300, there is no power sequencing issue. operation is simple. you
just press the TUNE button on the Radio or on the Tuner and it seems to do
the same thing. It can take several seconds to tune on a frequency for the
first time. It is a little loud, but much quieter than the KAT-500
Tuner.There is not much more to say about this tuner. I used an early
version of this with my Ic-7000 in a Mobile setup for a number of years. It
just worked flawlessly. I just bought the new one with hopes of installing
it for Mobile use with the IC-7300.
Summary

Both of these tuners can be used with the IC-7300. Operation of the
Elecraft tuner with the IC-7300 is a little confusing, but it works fine,
once you get the hang of it. Operation of the LDG IT-100 with the IC-7300
feels very natural and foolproof. It integrates as nicely as an internal
tuner. If you are buying a Tuner just for teh IC-7300, I would recommend
the LDG IT-100. If you are using the KAT-500, you probably already have it
to use with other radios.