No 12720, Monday 02 Sep 2019, Scintillator

ACROSS
1   Tie up fancy undergarment (6) INVEST {IN}{VEST}
4   Chemical substance that can fence a house? (8) COMPOUND [DD]
9   A blind test for infection (6) SCREEN [DD]
10 Shroud over established concern (8) INTEREST {INTER}{EST}
12 Fancied criminal aiding me (8) IMAGINED*
13 No even benefit to badly televised grasslands (6) VELDTS {TeLeViSeD}*
15 Go over some muddled logic to buy expensive stuff (4) GOLD [T<=]
16 Respecting antisubmarine companies (2,8) AS CONCERNS {AS}{CONCERNS}
19 Nitty-gritty about news studios revealed (3,3,4) INS AND OUTS {A+N&N+STUDIOS}*
20 Did he cause a red stain at Jallianwala Bagh? (4) DYER [C&DD]
23 Sharpest point blunted in parts (6) SHARES SHARpESt
25 Time to have idea for local layout (4,4) TOWN PLAN {T}{OWN}{PLAN}
27 Protection for illuminator? (4,4) LENS HOOD [CD]
28 No mother accepts stylish names in Latin (6) NOMINA {NO}{M{IN}A}
29 Familiar view next to passenger seat (8) NEARSIDE {NEAR}{SIDE}
30 Son breaking records gets grand treats (6) FEASTS {FEA{S}TS}

DOWN
1   Going forth, Iceland's taking to court (7) ISSUING {IS}{SUING}
2   Violent, evil Arabs – they keep changing (9) VARIABLES*
3   Reportedly find kiss to be beautiful (6) SCENIC (~see nick)
5   Noise of an animal? Alright to keep at home (4) OINK {O{IN}K}
6   Phantom's personality (8) PRESENCE [DD]
7   You hang in a balance and turn the other way (5) UPEND {U}{PEND}
8   Hates exams, half-dead at start (7) DETESTS {TESTS}<=>{DEad}
11 Allowance covers one working (7) PENSION {PENS}{1}{ON}
14 Power key on a keyboard (7) CONTROL [DD]
17 Income from sovereign bonds (9) ROYALTIES {ROYAL}{TIES}
18 Hen seems suspect, finding traps (8) ENMESHES*
19 Hormone protection stops at nothing (7) INSULIN INSULatIoN
21 Empty nester lets out, seeking a payment (7) RENTALS {Ne..eR+LEST}* over {A}
22 Returns from party upstairs, finding husband not home (6) INCOME {INC}{hOME} Why upstairs?
24 Apparently almost endless difficulty in breathing (5) APNEA {AP}{NEAr} AP/Apparently? See comments
26 Agreement with a detective agent (4) BOND [DD]

Reference List
Fancy = IN, Antisubmarine = AS, About = A, News = N, Point = PT, Time = T, Stylish = IN, Son = S, At home = IN, Nothing = 0, Party = INC, Husband = H, Apparently = AP

GRID