Takeout Doubles

Board 2
East Deals
N-S Vul
♠K 8
♥K 8 5 4
♦5 4
♣Q J 8 5 2
♠10 5 3 2
♥J 7 2
♦J 8 3 2
♣A 6
N
WE
S
♠9 6 4
♥A Q 10 9 3
♦A Q 10 9
♣3
♠A Q J 7
♥6
♦K 7 6
♣K 10 9 7 4
WestNorthEastSouth
  1♥Dbl
1♠2♣2♦3♣
All pass   
3♣ by North

South has an opening hand and tolerance for the unbid suits. North is strong enough to make a free bid, but not strong enough to bid game. North can bid 2 ♣ or 1 NT to show they have values. EW can now bid diamonds to show at least 5 hearts and 4 diamonds.
Lead is ♦ A against clubs and ♣ 7 against a heart contract.