Looked around and found the suicide cord, so I decided to quickly apply power to the 120B.
-Pat
Oh no you beat me to it !
I too got an HP 120B recently, meant to start restoring it pretty soon, was very excited to post about it, but too late you came first !
Mine is Gemra made, G245-00364. So S/N much older than yours, or is the S/N specifict to each and every manufacturing plant ?! That's something I have never been able to determine for my old Tek scopes.
Anyway yours look beautiful with this blue CRT !
I immediately notice that the caps look of a newer/ better type, so your unit might quite recent.
I mean I am looking at the two side byt side axial caps at the back of the trigger switch assembly, the type that always fails I gather... on mine they are completely rotten, but yours look brand new.
Other clue : the shield on your CRT looks new, the pain I mean... mine is badly flaking off !
I don't even know if mine will power up... it's missing half its tubes !
.. so no idea about phosphor colour, hey maybe I will get lucky and have a blue one like you ! No, not likely !
Anyway, looking forward to your restoration, and can't wait to start mine. Before I do anything with it, would like to buy a Variac as I can't afford to blow it.. have many Tek spares but only this one and only HP scope, zero parts handy to fix it if I screw up !