Hmm - this is definitely unusual! You shouldn’t see that error happen normally (we do many millions of test pulses now without issue). We don’t normally use a coax on the end out of concern from ringing etc - although I wouldn’t have expected damage to happen there. This happens if the tip is directly connect as well right (i.e., not the SMA cable opening)?
Before looking at HW issues it might be something easier to fix…
We realized there was a bug in the firmware for the EEPROM writing, causing many(!!) more writes than should happen in some use cases (specifically, if you are varying settings on each pulse it does an EEPROM write with them, which can kill the EEPROM. The faults also get saved to EEPROM so if the EEPROM isn’t working correctly it might never “clear” the fault.).
Luckily it’s almost always fixable with firmware - the new version of the firmware (working on now) now only writes when you request it. It also uses a different EEPROM page so everyone will be starting at “day 1” with their EEPROM lifetime (i.e., regardless of if you saw issues or not we’ve mapped out the problem EEPROM). The firmware is built “per unit” so will need your board id to build it - if you can email support -AT- newae.com we can open a case for you to get the details to you. There was another post on the forum with the update procedure as well, but we’re working on making it even easier…
Re - repair service if this doesn’t work. They could still be under warranty (it doesn’t sound like you’ve used them in a way I’d expect damage), but can contact you via email to sort out. We haven’t done out of warranty repairs yet but something we may… so far the (reported) failures have been low enough we haven’t had to sort that out yet!