Help with T7/400

Can somebody please help me to get The Tennis Channel . I know it is hidden
on T7/400 . I have T7 tuned up good, signal on channel 400 shows 90/85 but
all I get is a blank screen.... When I turn 4DTV (920) on and off it blinks
for about 2 seconds and is gone....
I would appreciate any help.
Regards,
Mike