It’s amazing to think that there are now more than 100 years’ worth of QSTs. In this review of articles from 100, 50, and 25 years ago, there are articles about 200-meter (1.5 MHz) operation,
Long-Distance 200 Meter Work (January 1920)
by Dr. Radio
Apparently, one of the biggest mistakes that amateurs made in tuning their spark-gap transmitters to transmit on 200 meters was that they chose the wrong size capacitors (condensers). The article notes,
One of the surprising things is the lack of appreceiation of condenser characteristics. It seems very difficult for many amateurs to resist the temptation to reason that if a small condenser is good a large one would be better. In several instances amateur stations have been found to be entirely out of resonance because of using a condenser whose large capacity gave the circuit a wavelength entirely beyond that of the antenna.
It goes on to recommend the use of “three jars of ordinary old-style Marconi condensers.”
A Coaxial Band Checker (January 1970)
by Lew McCoy, W1ICP
When I was a Novice, back in the 1970s, I really didn’t know what I was doing. It was amazing that I made and contacts at all. Apparently, I wasn’t alone. As W1ICP writes,
There are two common problems for the Novice that can result in no answers to calls. One of them is the lack of power actually reaching the antenna, and the other is calling on one band, but mistakenly listening on another. The last seems a little foolish, but believe it or not, it can happen quite easily, and often does.
The coaxial band checker was, therefore, designed to ensure that the Novice was transmitting and listening on the same band. “The unit,” W1ICP says, “will show you visually whether or not you are puttin gout on the correct band, and also give you a relative indication of power flowing through the line to the antenna.”
Getting the Most Out of Your T-Network Antenna Tuner (January 1995)
by Andrew S. Griffith, W4ULD
The T-network antenna tuner is arguably the most popular design out there. It’s used in both external and internal tuners. Frequently, though, there’s more than one combination of settings that will provide a match. W4ULD writes:
It’s usually possible to find more than one group of T-network settings capable of transforming a given load to 50 Ω. Some of these values may work better than others; some may even be worth avoiding altogether! Sometimes, a T-network components overheat or arc over; sometimes, it seems hard to match a garden-variety load even with a wide-range tuner. Let’s see if we can find out why.
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