A couple of days ago, out of curiosity, and feeling somewhat adventurous after imbibing copious amounts of amber liquid seeing in the New Year (yeah-yeah... I know - alcohol and test equipment don't mix), I decided to try and update (or more correctly, downgrade) my machine back to firmware v1.09 from v1.12. Firmware v1.09 was the firmware I was having trouble updating to from v1.08, months ago. There was no way back then that I could get v1.09 to run, I tried everything; multiple USB sticks of various sizes formatted with FAT, FAT32, many, many times - the machine just refused to boot after updating; it would hang with the TG and Auto buttons illluminated, but would not go any further. My unit has bootloader v1.02.
I initially considered sending my analyzer back for a warranty repair thinking there may have been a problem with it, but then decided against that and chose to stick with firmware version v1.08 until a newer firmware became available, which is the current v1.12.
Surprisingly, downgrading from v1.12, I was able to install v1.09 via the operating system of the analyzer (the Rigol update procedure) and it booted up without any problem at all; there was no hangup at boot with the TG and Auto buttons being illuminated, like there was when I was updating from v1.08 to v1.09, or updating to v1.09 from any one of the earlier firmware revisions I have (v1.06, v1.07, and v1.08). Whatever was preventing v1.09 from being installed properly was cleared after updating to v1.12.
The tracking generator only goes down to -20dbm on my unit with FW v1.09, (as it always had with all the previous versions of firmware including the original v1.05) unlike the -30dbm some others on the forum can have with v1.09. I suspect there's an anomaly or bug in the v1.09 firmware that affects certain hardware combinations allowing dropping of the TG output level to -30dbm on some machines, which is probably why Rigol addressed that in firmware v1.12. Anyway, I have again updated to the latest FW 1.12 without any problem. The "Version of Digital Board FPGA" was updated to 00.05 with firmware v1.12, whereas it became 00.04 when I downgraded to FW v1.09.
Tom