diff --git a/rx-angular/rx.angular.d.ts b/rx-angular/rx.angular.d.ts
index 413abf30b..9e76a95b6 100644
--- a/rx-angular/rx.angular.d.ts
+++ b/rx-angular/rx.angular.d.ts
@@ -14,7 +14,7 @@ declare module Rx {
     }
     
     export interface ScopeScheduler extends IScheduler {
-        constructor(scope: ng.IScope);
+        constructor(scope: ng.IScope) : ScopeScheduler;
     }
 
     export interface ScopeSchedulerStatic extends SchedulerStatic {