[Amps] grid resonance

[k7fm]

For those interested, see 
http://www.aade.com/lcm2binst/coilcraft%20L%20measurement.pdf

A number of inductance meters are tested in the article and it seems that 
many of them lie, because of the method used.  The article, by Coilcraft, 
also covers the use of grid dip meters.

My Millen manual mentions that a grid dip meter can be used to determine Q. 
As I recall, that is done by determining the width of the dip and 
calculating what frequency points are at some reference level.  Fairly 
crude, but at least the Q measurements are made on frequency.

Grid dip meters are fun instruments.  The old Heath was exceptional, since I 
could carefully couple it to an antenna, zero in on a repeater input then 
talk into the front panel.  The unit would fm modulate and I could make 
contacts on the repeater with just my grid dip meter.  If they have the 
right socket, they can be used to determine crystal activity - great for 
those who grind their own crystals.

if the circuit is right, it can also be used as a regen receiver or a diode 
receiver (when in the wavemeter mode).

73,  Colin  K7FM