Mark Sims wrote:
This type of circuit is NOT a free running oscillator. It is a type
of blocking oscillator that generates a short, high powered ping
every second or two. It is designed to be able to extract every bit
of power out of the battery. It can run for over a month off of a
couple of button cells, yet generate a signal detectable over a mile
away while it is laying flat on the ground. The allowable frequency
bands are at 216, 217, and 219 Mhz. Each unit must be on its own
freq, hence the need for one-off custom crystals.
Yes, it is a weird circuit and depends upon all sorts of unspecified
parameters. The components have to be hand selected and matched.
This is the price one has to pay for this sort of operation.
This is comparable, then, to the wildlife transmitters for Argos (which
are at 400MHz-ish).. Does this application need good medium term
stability (i.e. are you making a series of Doppler measurements?)
--------------------------------------- -Build a free running
Colpitts oscillator and get it tuned to the frequency you want.
Then, insert the crystal in series with theemitter.
_______________________________________________ time-nuts mailing
list -- [email protected] To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow
the instructions there.
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
