In a message dated 1/7/2005 3:53:20 PM Eastern Standard Time, jtml@lanl.gov
writes:
The Q meters that use resonance of a component against a known
standard capacitor or inductor are not so useful to measure unloaded
Q of a tank circuit. I am referring to the old Hp and Boonton Q
meters. They are used to measure Q of coils, DF of capacitors, and so
forth. Loaded Q of a tank circuit, i.e., with the tube plate
resistance at one end and the load Z at the other, can be calculated.
Unloaded depends on the quality of components, skin resistance,
connection integrity, etc. In VHF/UHF cavities, the unloaded can be
quite high.
73
John
K5PRO
I thought that Q meters like the Boonton are exactly what is needed to
measure the unloaded Q of a tank circuit at the operating frequency. That is
what Q
meters do, they measure the unloaded Q or quality factor of a particular
inductor or tank circuit at a particular chosen frequency. Measuring the loaded
Q
of a circuit is a different story. 73 Todd Roberts WD4NGG
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|