>From: Patrick Washburn
> I know nothing about electronics, but instead of replying on the trigger
> head to transmit the signal in real time and be limited by the physics of
> wireless transmitting, why not have the trigger record the time on a RAM
> chip or something built into the timer head and then transmit the recorded
> signal at the more leasurly wireless pace? (I am assuming that
> the rate of
> wireless transmitting is limiting the replution.) Would result in but a
There are techniques that can be used to transmit a non time stamped signal
and have more than enough accuracy. Basicly the same thing that used to be
done by radio stations, "at the tone, the time is...pause...beep". If the
base station knows that the transmitter will send a message and then an
accurately delayed (easy to do) pulse, it can be ready to capture the pulse
with accurate timing.
It might be easier to send a time stamped signal.
The stability and accuracy of the clock frequencies would determine how
often the clocks need to be synchronized. If they are accurate enough, you
could carry all the remotes over to the master clock to be synchronized in
the morning and ignore them throught the day.
If you put both transmitters and receivers (reasonably low cost data
transmitter/receiver modules are available) in the remote units as well as
the master unit, you can have the master unit send a synchronizing signal
periodicaly during the day to keep the times more accurately. All the
remote units would listen to the frequency of the master system so that they
all synchronize off the same pulse. Once you have bidirectional
communications, you can even have the remotes report any corrections that
they made so that you can verify the accuracy or correct it.
> resolution you want. Just a dumb suggestion from someone who
> doesn't really
> know what he's talking about.
You knew enough about it to understand the idea of time stamped messages to
eliminate real time monitoring of the signal.
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