Experiments with Co ils and Q-Measurement Wes Hayward, w7zoi, October, 2007 (Updates 01Dec07, 08Dec08.) I recently became interested in building a “Zero Power Receiver ( ZPR)”, a circuit that would receive the AM broadcast band while using no external power. There would be no batteries or other sources of energy.
Q Measurement with the AIM4170 revised 7-22-08 Summary: The AIM4170 can be used to determine the Q of coils and of tuned circuits. A function is included in the program to measure the Q of series and parallel tuned circuits. The Q of coils can be determined by noting the ratio of the reactance to the series resistance at any frequency.
wound 40 meter loading coil as 60 ohms. This leaves an inductor loss resistance of 9 ohms, so the coil Q = 2p(7.2)(18.5)/9 = 93. Since the 20-meter antenna is now a 1/4 wavelength center-loaded antenna on 40 meters, some rough calculations indicate that the antenna radiation resistance should be about 25 ohms. With 9 ohms of loss resistance in, The looped wires around R13 form a coil and R43 is added to lower the Q of that coil and prevent instability around the amplifier chain which occurs without the R25 addition. In the Q meter tested, the division ratio was held quite constant up to 40 MHz with a.
10/12/2013 · Experiments with Coils and Q-Measurement Wes Hayward, w7zoi, October, 2007 (Updates 01Dec07, 08Dec08.) – ZPR (Zero Power Receiver, HP 4342A) Fun with Tubes – Test Equipment: The Neglected Q Meter. -, Q Measurement with the AIM4170, AN EXPERIMENTAL Q METER, AN EXPERIMENTAL Q METER, AN EXPERIMENTAL Q METER
