Each of sixteen clues contains one misprinted letter in the definition part. Corrections of misprints spell the name (three words) of a 1A, contents of which are given by five unclued lights (including two as a pair). The 1A’s name also describes the location in the grid of its contents in relation to two other unclued lights.
 

Across

 
5    Turn reptile around in silence (6)
9    Changed vote around end of transmission (10, three words)
14    Board beginning without director (3)
16    Free love stopped by force (6)
17    One in new question referring to magic square (5)
20    Showy woman once in a drama excited many (7)
22    General unsettled spell (7)
24    Good storage device joined tubs (7)
25    Tipple with a scone (5)
26    Trick involving square cloth (5)
28    Leaked objection inside worried department (7)
31    Be hesitant, short of energy, coming into shelter in port (7, two words)
33    Particular enthusiast, one in train going west (7)
37    Approach work in court (5, hyphened)
38    Expression of disapproval non-smoker favours (5)
39    Sporting failure, on reflection, I admitted (6)
41    Shrink from translation of trashy epic (10)
42    Norse island custom (6)
43    Each stain apprehended by extra attentiveness (8, two words)
 

Down

 
1    Shop assistant opposing drill… (13, hyphened)
2    …and cold comfort (5)
3    Chip? Brown on edge, not black (6)
4    Smirker unusually riled (5)
6    Notice complicated delta, comb-shaped (7)
7    Referring to pasha, European plans journey (6, hyphened)
8    Central part of Mexico almost full (4)
10    Sailor on coaster? English salt (6)
12    Teach, in flat area, certain dance (13, three words)
13    Sin, say, sadly ensnaring an ascetic (8)
15    Signaller following wreckage covering miles (7)
23    Likely to receive dry mutton, cry (7)
27    Catches net awkwardly on raised pole (7)
30    Polished tip in plant (6)
32    Crops near hotel picked up and delivered (6)
35    Firm friend, not a philosopher (5)
36    Upset fool over bones (4)
 
A first prize of £30 for the first correct solution opened on 2 March. There are two runners-up prizes of £20. (UK solvers can choose to receive the latest edition of the Chambers Dictionary instead of cash— ring the word ‘Dictionary’.) Entries to: Crossword 2198, The Spectator, 22 Old Queen Street, London SW1H 9HP. Please allow six weeks for prize delivery.