{"id":170,"date":"2015-11-19T01:30:42","date_gmt":"2015-11-19T00:30:42","guid":{"rendered":"http:\/\/www.ik0vve.net\/?page_id=170"},"modified":"2023-11-22T10:44:29","modified_gmt":"2023-11-22T09:44:29","slug":"630-meter-band","status":"publish","type":"page","link":"https:\/\/www.ik0vve.net\/?page_id=170","title":{"rendered":"630 meter band"},"content":{"rendered":"

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Remote MF antenna variometer<\/h2>\n

In the video I show you the tests on the renewed 630m band variometer. I’ve changed the old motor with another with gearbox ratio of 1:30 so to get a better resolution during the antenna tuning. It’s possible a continuous variation of the speed, too.<\/p>\n

The pot is used to change the resistance to a simple 555 circuit so to change the speed of an astable configuration circuit. The squared wave goes to a little and cheap driver for bipolar stepper motor (indeed, my motor is unipolar… but\u00a0is possible to use as bipolar).<\/p>\n

In the next days the variometer will go near the base of the new antenna that at the moment is lying on the roof.<\/p>\n