I took out one of my old z-12's run a static session for opus. I ran the session on Friday and the unit sat in the office till Monday. When I went to download it there was no data there, only a photo.dat file. Has anyone ever had this happen before or have any suggestions as to what my have happened? Thanks.
I no longer own a Z-12, but my initial guess is that the internal batteries that support the RAM have died, which meant your data went *poof* as soon as you disconnected the external battery. The internal batteries are typically lithium primary cells that have a lifetime of 10 to 20 years or so, which means it's common to see '90s-era receivers losing backup power these days.
Q: did you check the file size realtime? Was there data on Friday?
If the unit boots with current settings and locks on sats quickly, then it retains ephemeris/setup data. That would demonstrate batt health.
If I recall correctly the memory goes "POOF" if the switch is thrown, even if the battery is still connected. You want to start a new file, disconnect the antenna, leave the unit on and get back to the office without delay.
Paul in PA