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Surprisingly it was not that easy to find a suitable switch, which switches between several states. After little research I thought I have found the right one with the ArcolectricSlide by Conrad Electronics. But it turned out that this slider switch is not connecting two opposite pins, but is respectively connecting each adjoined pins.

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Out of this, I came up with following scheme, to be able to switch between atleast three antenna lengths instead of five which the slider switch originally had. BTW three antenna lengths turned out to be perfectly fitting for a reasonable read distance calibration. As a side effect, one complete line of pins were not used, and therefore could be bend over for fixation.

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In order to achieve a bigger effect of switching between the three different antenna lengths, the antenna of this RFID tag has got six windings. As you can get out of the scheme, there are two middle postions of the switch, connecting the same antenna winding. But overall it works surprisingly well and has a noticable effect on the read distance.

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