Official calls
 

What is the proper mechanics for citing an illegal screen and delay of game warning??

Illegal screen is a blocking foul and delay of game, there is no real mechanic so to speak. You let that coach know and also the table.

Illegal Screen: Assuming the team is in control of the ball, you blow your whistle and raise a fist to signal a foul. You then do the "punch" mechanic to signal a team control foul. Then report the foul at the table, using the block signal.

DoG Warning: I do not believe there is a specific mechanic, I just blow the whistle with an open hand in the air, yell out delay of game and reasoning, making sure the coach and the table know.

If you are going strictly by NFHS mechanics, then the proper sequence for an illegal screen depends upon whether or not it is a team-control foul. It doesn't have to be. For example, it could take place during a throw-in.

As others have said the NFHS signal is the same as a blocking foul.
If it is a team-control foul, you first use the first in the air, then give the punch signal, then also give the blocking signal on the court, then indicate the spot of the foul. You would do the same when reporting at the table. This is outlined in last year's NFHS preseason guide on page 5.
If the foul is not a team-control foul, then just leave out the punch signal.


The delay of game warning is simply reported to the scorer who records it in the official book and also reported to the coach. It is all verbal and after sounding the whistle and putting up an open hand to stop the clock, if necessary, there is no mechanic. Just go to the reporting area and speak.
BTW since this is not a foul, the officials would not switch.

Re:delay of game warning, the official stops the game, goes to the scorer and makes sure that the scorer records the warning on the game sheet, and then goes to the head coach of the team being warned and informs him/her of the warning.

Case book play 8.1.1SitB.

Or a jump ball. Or a rebound.