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Posted by uzzors2k on Monday 13 February 2017 - 18:20:51
I was wondering how one should go about tuning a QFH antenna by measuring it's return loss. Has anyone attempted this? I have this idea that if I move...
Posted by uzzors2k on Monday 13 February 2017 - 18:20:51
...new I wouldn't get the antenna right without some tuning afterwards. So from my plots, it would I appear I've improved the selectivity. Is there any w...
Posted by alan sailer on Friday 25 November 2016 - 22:59:32
...across the MOSFET. I'm guessing it is part of the tuning for the unit. If so is it a worthwhile effort to try various values both higher and lower?
...
...ght want to add taps to the primary to adjust the tuning easily. So far you are on track....at least it fired. Keep going and experimenting. I have...
...ght want to add taps to the primary to adjust the tuning easily. So far you are on track....at least it fired. Keep going and experimenting. I have...
...g to mitigate the stress on the tube with further tuning and adding a fixed 5kohm and using the 5k rheostat to trim.
I have a mo fan blasting on th...
Posted by orac12 on Monday 18 April 2016 - 10:12:39
You should definitely add a breakout point to the top. It helps tuning especially if you're still much out of tune. Then play around with your primary...
Posted by Cool Dude Clem on Tuesday 10 February 2015 - 03:30:26
...decided to do something insane and get an air-gap tuning capacitor from an old junked radio, submerge it in oil and use that. It does work and I can ...
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