A 1.8:1 Is Good Enough... a Second Tuner Solves the Wrong Problem

A lot of hams see a remote tuner reach about 1.8:1 on one band, then watch the internal tuner pull that down to 1.1:1, and immediately assume the station must now be working better. On paper the number looks nicer. In practice, that conclusion is often too simplistic.

If a remote tuner such as an SGC-230 already gets the system to around 1.8:1 on 20 meters, that is usually not a harmful mismatch on HF. In many stations it is already well inside the range where the transmitter remains comfortable and the extra mismatch loss is very small. The internal tuner may still make the transmitter see a more flattering number, but that does not automatically mean more useful RF is reaching the antenna or being radiated better.

The first correction: matching losses are often small on HF... but not magically zero

The common statement that matching-network losses are “negligible” on HF is directionally right, but only when kept in context. With decent components, moderate impedance transformation, and a sensible operating frequency, tuner losses are often small enough that they are not the main thing holding the station back. That is especially true when comparing a mild mismatch like 1.8:1 to a near-perfect 1.1:1.

But small is not the same as zero. Matching devices can become noticeably lossy when the impedance transformation is extreme, the circulating currents are high, the inductors or ferrites are undersized, or the network is working against a highly reactive load. So the right statement is not that tuner losses never matter. The right statement is that on HF, with a modest mismatch and a healthy tuner, they are often small enough that obsessing over the last bit of SWR is misplaced.

The second correction: a 1.8:1 match at a remote tuner is usually not harmful

There is nothing inherently dangerous about a 1.8:1 SWR in an HF station. Most modern transmitters tolerate that without complaint, and many radios will happily run there all day long. If the remote tuner has already reduced the mismatch to that level, it has done the hard part.

The real danger zone is not “anything above 1.0:1.” The real concern is whether the mismatch becomes high enough to cause transmitter foldback, excess stress, or large standing-wave voltages and currents in places where you do not want them. A 1.8:1 reading is normally nowhere near that kind of drama.

That is why it is important not to treat every non-perfect SWR number as a problem that still needs solving. On HF, a remote tuner landing at 1.8:1 often means the system is already operating in a perfectly acceptable region.

What the internal tuner does... and what it does not do

Once the remote tuner has transformed the antenna system as well as it can, the internal tuner at the radio end is mostly dealing with what the transmitter sees at its own port. That can be useful for the radio. It can make the rig happier. It can prevent power reduction in radios that are fussy. It can make the display read 1.1:1. But that is not the same thing as improving the antenna system itself.

This is the key point: the internal tuner does not go back through the coax and somehow improve the match at the remote tuner output or at the antenna feedpoint. It only transforms the impedance again at the shack side. So if the external tuner was already doing a decent job, the second tuner mostly improves the transmitter’s view of the system, not the radiator’s actual behavior.

That is why saying “I now have two tuner losses” is not completely wrong, but it misses the more important conclusion. Yes, a second matching network can add a bit of extra loss. But more importantly, it is usually adding that loss to achieve a cosmetic improvement in SWR rather than a meaningful improvement in radiation.

Why chasing 1.1:1 after 1.8:1 is usually the wrong optimization target

On paper, 1.1:1 looks better than 1.8:1. In real operation, that difference is often so small that you will never hear it on the air. What you will hear more easily are changes caused by antenna placement, height, feedline routing, common-mode current, radial quality, nearby conductors, and band conditions.

That is why an internal tuner following a remote tuner often becomes a “meter prettifier.” It may satisfy the radio, but it usually does not turn a mediocre antenna system into a good one, and it usually does not turn a decent system into a dramatically better one either.

In fact, adding a second tuner can sometimes make troubleshooting less clear. The transmitter sees 1.1:1, the operator assumes everything is perfect, and the real issues remain hidden elsewhere in the chain. A very nice number at the rig tells you surprisingly little about current distribution, balance, feedline radiation, or the actual efficiency of the radiator.

When the internal tuner can still make sense

There are still cases where using the internal tuner after a remote tuner is reasonable.

• If the radio begins to fold back power above a certain SWR, the internal tuner can help keep the transmitter in its comfort zone.
• If the feedline section back to the radio is not especially short and the rig is sensitive to mismatch, the internal tuner may make operation more convenient.
• If the goal is simply transmitter compatibility rather than measurable field-strength improvement, then using the internal tuner is a practical choice.

But that should be understood for what it is: transmitter-side convenience, not a major gain in antenna-system performance.

The more useful engineering view

A remote tuner near the antenna is valuable because it moves the main impedance transformation away from the shack and closer to the radiator. That is usually the smart place to do the heavy lifting. Once that remote tuner has already brought the system into a mild-mismatch region like 1.8:1, the battle is largely won.

At that point, trying to flatten the last bit of SWR with an internal tuner is usually not where the biggest gains are hiding. The bigger questions are these: Is the radiator efficient? Is the installation symmetrical enough where needed? Is there unwanted feedline current? Is there excess ground loss? Is the antenna too low? Is the surrounding structure dominating the result?

Those are the questions that tend to decide whether the station actually performs better. The step from 1.8:1 to 1.1:1 usually does not.

Conclusion

If your remote tuner already lands around 1.8:1 on 20 meters, that is generally not harmful on HF. The mismatch loss is small, the tuner is already doing its core job, and the station is likely much closer to optimum than the SWR perfectionists would suggest.

Using the internal tuner to pull that down to 1.1:1 is usually not useless in the strict sense, because it can help the transmitter remain happy. But it is often useless as a performance obsession. It mostly improves the number seen by the radio, not the actual effectiveness of the antenna system.

The practical takeaway is simple: if the remote tuner is already around 1.8:1 and the transmitter is happy, there is usually no meaningful reason to chase 1.1:1. On HF, that effort is often solving the wrong problem.

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