User`s manual

- 13 -
Using Your Eggtimer TRS with the Eggfinder LCD Receiver
The Eggtimer TRS is designed to be used with the Eggfinder LCD receiver. In addition to the
same GPS coordinate functions that you get with an Eggfinder TX transmitter, you can also use
the Eggfinder LCD to program your Eggtimer TRS’ flight settings, check the status of the
computer battery and the deployment channels, test the deployment channels (see the Appendix),
and during your flight display the real-time altitude from the pressure sensor and the status of the
deployment channels.
The Eggfinder LCD receiver actually acts as a dumb display terminal, similar to the USB cable
attached to the data port with a terminal program. All of the data actually comes directly from
the Eggtimer TRS, nothing is stored or saved on the LCD receiver itself. If you change
something and get a confirmation, it’s coming directly from the Eggtimer TRS unit, so you can
be sure that it really did get changed.
Note: Eggfinder LCD software version 1.09d is the minimum release that supports programming
the Eggtimer TRS. Earlier versions will display the GPS coordinates, but they will not show the
altitude or deployment channel status in-flight. If your Eggfinder LCD receiver has an earlier
version of the software, please download the latest version from the Eggtimer Rocketry web site,
www.eggtimerrocketry.com .
Also, if you have not done so already you will probably want to install an external push button
on your Eggfinder LCD receiver rather than using the internal push button. You can find
instructions for doing that at the end of the Eggfinder LCD Assembly and User’s Guide on the
Eggtimer Rocketry web site ( www.eggtimerrocketry.com ).
Pairing the Eggtimer TRS and Eggfinder LCD
When you turn on your Eggtimer TRS, it sends out a “beacon” that tells the Eggfinder LCD
receiver “Here I Am”. If you have just turned on your Eggfinder LCD receiver and let it go
through the banner (5 seconds) and local status display (10 seconds), you will see a screen that
says “Waiting for Sync”. The Eggfinder LCD receiver listens for the beacon signal from an
Eggtimer TRS on the same frequency and ID code. If it gets one, it “pairs” with the Eggtimer
TRS, acknowledging the beacon and going into terminal mode. The Eggfinder LCD receiver
then displays the software version and Device Name of your transmitter so you know that it’s
YOUR Eggtimer TRS and not somebody else’s. The Eggtimer TRS and Eggfinder LCD remain
in terminal mode until you either tell it to start a flight, or go into Halt mode.
If the Eggtimer TRS doesn’t get a response back from an Eggfinder LCD receiver, it assumes
that none is present, and it goes on to the cable programming mode. If it doesn’t see a cable
within 30 seconds, it assumes that you’re sitting on the pad waiting to launch, so it starts the
launch sequence.
When you first turn on your Eggtimer TRS and your Eggfinder LCD receiver (which should be
done within 45 seconds, so the pairing doesn’t time-out), you will see this screen:
Eggfinder RX LCD
Version 1.09d