question about radar

[bombata]

hi all,

i play the japanese side in the "war in the pacific" scenario and was surprised to see some japanese DD with radar technology!

now, if i put this DD in a CV-TF, do they improve the CAP of the TF, so more fighters can be sent against an enemy air attack?

if not, from which periode of the war the japanese get realy usefull radar systems to detect allied aircrafts and to improve they CAP in land bases AND TF?

bye