The Sunday Crossword, Sunday 29 Jan 2017

ACROSS
1   Fruitful development of clearest system for measuring quakes (7,5) RICHTER SCALE {RICH}{TER SCALE*}
9   Bound to turn round new board (5) PANEL {N} in {LEAP<=}
10 Justify being very mean (9) VINDICATE {V}{INDICATE}
11 Overthrow leader in disgrace and rest, right away (6) DEPOSE {Di...e}{rEPOSE}
12 Lion grew terribly menacing (8) LOWERING*
14 Make more efficient version of metal siren (10) STREAMLINE*
15 Benefit from place with our team (4) PLUS {PL}{US}
17 Curse love at end of speech (4) OATH {O}{AT}{s...cH}
18 Aspect of expert in person (4,2,4) FACE TO FACE {FACE T}{O F}{ACE}
20 Recurring image about revolutionary party with rage (8) PERIODIC {P{IRE<=}{DO<=}IC}
21 Son takes out gifts (6) SKILLS {S}{KILLS}
24 Promise to get gold back, surrounded by relative support (9) GUARANTEE {G{AU<=}RAN}{TEE}
25 Pin in shadow, elusive (5) DOWEL [T]
26 Sentimental stuff I start about bygone pie (7,5) CORNISH PASTY {CORN}{I}{SH {PAST}Y}

DOWN
1   Express rebuke over identification (5) RAPID {RAP}{ID}
2   Scheming and playing ironic part also (14) CONSPIRATORIAL*
3   Chap after endless chat is showing charm (8) TALISMAN {TALk}{IS}{MAN}
4   Party needing some extra vehicles (4) RAVE [T]
5   Baffled fool set up (10) CONFOUNDED {CON}{FOUNDED}
6   Dally with one in group with hesitation (6) LOITER {LO{1}T}{ER}
7   Actor wades in, ideally trained (6,3-5) DANIEL DAY-LEWIS*
8   Song in clip with guys dancing with energy (5,3) PEGGY SUE {PEG}{GY SU*}{E}

13 Shabby field with portion over time engulfed by marsh (4-6) FLEA-BITTEN {F{LEA}-{BIT}{T}EN}
14 Work quietly during present strike (8) STOPPAGE {ST{OP}{P}AGE}
16 Invented company with approval excited dupe (6,2) COOKED UP {CO}{OK}{ED UP*}
19 Recording absorbing account in principality (6) MONACO {MON{AC}O}

22 Odds on bet spread out (5) SPLAY {SP}{LAY}
23 Not so much praise without bishop (4) LESS bLESS