allanhurst:
1/ Except the pager industry in GB disappeared many years ago with the advent of 2G mobile phones! I worked on them as well....2/ No. It's a series resonant LC circuit which appears capacitive if tuned one way - which increases the system resonant frequency, and vice versa - (inductive - reduces it), at this nominal frequency.
At resonance it appears as a short circuit.You can model a crystal as a high inductance ( eg 5mH ) in series with a very tiny capacitance. This can be measured with a special instrument, together with it's equivalent series resistance R - a few ohms..
This has a resonant frequency. Adding series inductance decreases it, capacitance increases it.F = 1 / (2pisqrt(L*C)
-
I was being sarcastic about pagers and job security, but I figure the basics can be applied to more advanced technology.
-
To recap, you would measure L and C of the crystal and add an L or C to tune the crystal to its desired frequency. That seems tedious if you were measuring each crystal and selecting appropriate L or C values. I am not using this for communication, so staying on sync doesn't really concern me; I will just measure the crystals speed, the clock cycles between my two pulses, and divide to get time. Did you do anything to decrease the variance of the crystal; the random noise in the system? Or is that simply the limit of the crystal you are using? I hope I am saying the correct word. I would hate to be mistaken again.