OK so it looks like I messed up an F510. I was programming it and sent a data file to it while I was in 'maker reserve' mode and I don't have the original .icf clone file - yes I know, schoolboy error
When I power it on now the freq/channel just flashes (PLL unlocked?)
I have v1.0 of the F500ADJ software but when I run it, it says 'Version number does not match for this transceiver' so I'm assuming there is another version.
Does anyone now of a factory reset procedure or have a working .icf clone file for one of these radios that I could use as a starting point to reprogram the radio and get this thing going again?