so this maybe a stretch but,
the 4 Q device test posts.
Device Test = Detectives
leaving E, X, C, and possibly a blank (1st post no letter)
also there was only one t that was capitalized → T
some reason the unexplained Q & A came to mind → A
EX_C_ + T + A = EXACT
EXACT DETECTIVES
MW definition
EXACT:
transitive verb
1 : to call for forcibly or urgently and obtain
from them has been exacted the ultimate sacrifice —D. D. Eisenhower
2 : to call for as necessary or desirable