Dear OM, Your three Q measurements indicate that your measurement techniques are sound - unlike mine! It occurs to me that I could use my HP vector impedance meter to measure Q using the series reson
Hello Dick, I used this method and two other ones to measure the Q of my loading coil. The coil can be seen on page 62 and on the cover of the LF Handbook (the caption of Fig. 4.17 at page 62 describ
To All from PA0SE What you really want to know is the equivalent series resistance of the coil. I usually do this as follows: Connect generator to meter and measure ampliude V1. Then connect a series
Hi Jim and LF Group My 136kHz coil is a rewound Decca coil with two layers of coil and the original variometer, which was also rewound. This gives a coil with an inductance variation of 1.7mH to 2.2m
Recently I described some experiments with multilayer coils based on a Decca coil. The resultant coil is now similar to that shown in the LF book, page 13 (See the second coil back) except my coil h
In a message dated 11/21/01 8:35:15 AM GMT Standard Time, [email protected] writes: I connected the coil under test with a parallel air-spaced capacitor to the signal generator via a variable capa
Dear all, I have measured the loss of my aerial variometer with the same resistive bridge which I use to measure the feedpoint resistance of my LF arial (two resistors 150 ohms from the feed point to
Dear Peter, LF Group, This is one of the well-known techniques for measuring Q; as Rik pointed out, the important thing is to minimise coupling between generator and detector and the tuned circuit un
Further to Peters experience, I have used the same method:- ie lightly couple a sig gen into the coil (I use a single turn of wire ) resonate to the required freq. and find the 3db points with an osc
Hello Peter, your method seems be OK, the losser (more loss ?) the coupling is the more accurate the Q-measurement. But keep in mind the the Q of a coil is frequency dependent, due to skin-effect, pr
Recently I described some experiments with multilayer coils based on a Decca coil. The resultant coil is now similar to that shown in the LF book, page 13 (See the second coil back) except my coil ha
