what’s wrong with my F1 Chrony,help.

Everything seems to be working normally, excerpt from the manual available on their site:
1. TURN UNIT ON. If you purchased the Chrony in the United States, it will automatically record and read in feet per second (FPS). If you purchased it in a country that uses the metric system, it will record and read in metres per second (MPS).
2. A F-1 Chrony will display AL with the flashing symbols on each side. . These flashing symbols indicate that the unit is working and is ready for use. For units that are set to read in MPS, the display has a dot between the two letters (e.g., A.L) with flashing symbols on each side; without the dot (e.g., AL) the unit readout is in FPS.
3. You cannot change the standard of measure on the F-1 and M-1 Chrony units. The F-1 Chrony will show AL in FPS and the M-1 Chrony will show A.L in MPS.
4. The F-1 and M-1 Chrony and the respective Master Chrony units report only the shot number and shot velocity up to 32 shots. Record on paper each shot number and velocity, as these units do not have a memory. After the 32nd shot, Ln appears, and the velocity readout flashes. Shot 33 and all subsequent shots report as shot 32. To start a new string, turn the Chrony OFF then ON again.

Are you shooting under a cloudy sky with the diffusers installed? If so, take them off. If you’re still not getting a readout, you just don’t have enough light. As a general rule, use the diffusers under a clear sky, and take them off if it’s cloudy but bright. Good luck. And just in case, here’s Shooting Chrony’s web site: http://www.shootingchrony.com/products_NEW.htm

Dave

Did you take a shot through it, and see what happens 😆 Maybe reading the manual will shed some light on the subject 😉 .

Replace the battery.