Power reserved first handset (6,7)
I believe the answer is:
remote control
'handset' is the definition.
(I know that handset can be written as remote control)
'power reserved first' is the wordplay.
I cannot quite understand how this works, but
'power' could be 'control' (control is a kind of power) and 'control' is found in the answer.
'reserved first' could be 'r' (1st letter of 'reserved') and 'r' is located in the answer.
The remaining letters 'emote' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for remote control that I've seen before include "Electronic device" , "Electron motor? (anag)" , "Portable device for operating TV etc" , "gadget" , "TV accessory" .)