We started a sequence of scheduled transient hardware injections with burst waveforms on September 3 (LLO aLOG 20246, LHO aLOG 21186) with the intention of testing the basic operation of the low-latency burst analysis and the EM follow-up event selection logic.  It was done with the inverse actuation filters left over from ER7, so we didn't expect accurate injection of the desired strain waveforms, but that was OK for the purpose at the time.  However, we woke up the next morning to find that one of the injected coherent signals had been unexpectedly loud.  (Another injected coherent signal, though, was fine.)  Investigations of that anomalous event have been collected at https://wiki.ligo.org/LSC/JRPComm/G181472.

No further transient hardware injections have been done since then (LHO aLOG 21202, LLO aLOG 20254).  However, we are planning to resume burst hardware injections, restricted to fairly low frequencies, soon.