... by: numpl_npm

-(1234)AB89 and
 (only one of 1234 in HJ7)

Then maybe solved with DFC and CFC
 DFC: Digit Forcing Chains
 CFC: Cell Forcing Chains

... by: numpl_npm

This puzzle is SE11.9, but not so hard.

| _ 2 _ | 3 _ _ | _ _ _ | A
| 4 _ _ | _ 1 _ | _ _ _ | B
| _ _ 9 | _ _ 5 | 8 _ _ | C

| 1 _ _ | _ 2 _ | _ _ _ | D
| _ _ 5 | _ _ 9 | 7 _ _ | E
| _ 3 _ | 5 _ _ | _ 4 _ | F

| _ _ _ | _ 5 _ | 6 _ _ | G
| _ _ 6 | _ _ _ | _ _ 7 | H
| _ _ _ | _ _ 7 | _ 8 9 | J

Exocet J3 H6 [1234]G89

[1234]J3 [1234]H6
(x)GJ3 where (x in 1234) -> -(x)GH6
(x)GH6 where (x in 1234) -> -(x)GJ3

[78]G3 ->
| (12)GH6 -> contra. with basics
| (13)GH6 -> contra. with basics
| (14)GH6 & -(14)J3 -> contra. with basics
| (23)GH6 & 1J3 -> contra. with basics
| (23)GH6 & 4J3 -> contra. with basics
| (24)GH6 -> contra. with basics
| (34)GH6 & -(34)J3 -> contra. with basics

8G6 ->
| (12)GJ3 -> contra. with basics
| (13)GJ3 -> contra. with basics
| (14)GJ3 -> contra. with basics
| (23)GJ3 -> contra. with basics
| (24)GJ3 -> contra. with basics
| (34)GJ3 -> contra. with basics

-(78)G3 & -8G6 ->
| (12)GJ3 & -(12)GH6 -> contra. with bellow 1 DFC
| | 8AD6=[8A6 -8A3|8D6 -8F5]=8F3
| (13)GJ3 & -(13)GH6 -> contra. with basics
| (14)GJ3 & -(14)GH6 -> contra. with basics
| (23)GJ3 & -(23)GH6 -> solved with bellow 2 DFCs
| | 7BF4=[7B4 -7B3|7F4 -7F5]=7F3
| | 3E89=[3E8 68E29 6A1|3E9]=6B9
| (24)GJ3 & -(24)GH6 -> contra. with basics
| (34)GJ3 & -(34)GH6 -> contra. with basics

DFC: Digit Forcing Chains

... by: James Havard

My mistake, my middle box row solution is basics, not singles. Sorry.

... by: James Havard

463 subs and 543 seconds to find two subs in the top box row that together gives a singles solution A5=7 C4=4.
Middle box row 228 subs and 228 seconds to get three subs together for a singles solution D5=8 E1=2 F9=1
Bottom box row 42 subs and 67 seconds to get three together for a singles solution G6=1 G8=2 H4=2

... by: Frans Goosens

With trial and error

Combination A3=178 and F6=168

************************************************************
A3=1 F6=1 No solution, Fixed

Combination 2-digits cells

C2=6 No solution, Undo calculation
C2=7 Wrong, Undo calculation
C2=6 No solution, Fixed
C1=3 No solution, Undo calculation
C1=7 Wrong, Undo calculation
C1=3 No solution, Fixed
B3=7 Wrong, Undo calculation
B3=8 Wrong, Undo calculation

All reset to initial position

************************************************************
A3=1 F6=6 No solution, Fixed

Combination 2-digits cells

B3=7 Wrong, Undo calculation
B3=8 ( F3=7 ) Solved,


#440--------------------------Solution
020 300 000-------------621 378 495
400 010 000-------------458 912 376
009 005 800-------------379 465 812

100 020 000-------------164 723 958
005 009 700-------------285 149 763
030 500 040-------------937 586 241

000 050 600-------------793 851 624
006 000 007-------------816 294 537
000 007 089-------------542 637 189

Total solving time is : 185 sec.
Number of logical steps is : 15072