Nico, manual tuners normally have a "tune" position, which engages some sort of SWR bridge. When the SWR bridge in engaged, the rig sees a maximum SWR that does not exceed? between 2:1 and 3:1 (depending on the SWR bridge employed),? irrespective of the fact that the actual SWR seen by the tuner is 2:1 or 100:1. The low SWR (2:1 to 3:1) you see in the tune position while tuning will NOT kill your QMX finals, even at full power.
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You just key down your QMX with the tuner in the "tune" position, e.g. by using the "TUNE SWR" function in your QMX or by using a key, and turn the knobs to reduce SWR to a minimum (in most manual tuners this is achieved when a high-brightness? LED gets zero current through it).
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I have used exclusively homebrew Z-matches with my QMX and QMX+. I start by turning the knobs until the background noise is maximum (no key down), then I engage the tune position in the tuner and I simply key down at full power for a few seconds at a time, adjusting the knobs to get the LED brightness off. Then I get back to the "tx" position and start operating.
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Tuning can take up to half a minute or more with a new antenna, and sometimes I cannot get the LED off completely (meaning that the SWR is between 1:1 and 2:1 normally), but I have never blown a single QMX final.
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My2Cents
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72/73 de Enzo M0KTZ
