Question
 

Where can I find information on any act that is clearly intended to cause B encroach is an unsportsmanlike foul? Can't find any references.

Wouldn't that just be a false start?

I've never heard of disconcerting acts by A causing B to encroach. There are disconcerting acts by A such "where's the tee" or "wrong ball", but they aren't designed to cause encroachment.

Case play 9.5.1 B deals with acts by B only.

I think that's because there's no such ruling or interpretation.

I believe ANY ILLEGAL act causing B to encroach is considered a "False Start" by the offensive player generating the act. No such behavior elevates itself to the USC level.

Going back a few years on the electronic copy I have of the NFHS Rule book (2012).....assuming this is what he stumbled across.

Let the backpedaling begin in 3........2.........1.....


SECTION 5 NONCONTACT UNSPORTSMANLIKE CONDUCT BY PLAYERS

ART. 1 . . . No player shall act in an unsportsmanlike manner once the game officials assume
authority for the contest. Examples are, but not limited to:
a. Baiting or taunting acts or words or insignia worn which engenders ill will.
NOTE: The NFHS disapproves of any form of taunting which is intended or designed to embarrass,
ridicule or demean others under any circumstances including on the basis of race, religion, gender
or national origin.
b. Using profanity, insulting or vulgar language or gestures.
c. Any delayed, excessive or prolonged act by which a player attempts to
focus attention upon himself.
d. Using disconcerting acts or words prior to the snap in an attempt to interfere with A’s signals
or movements.
e. Kicking at the ball, other than during a legal kick.
f. Leaving the field between downs to gain an advantage unless replaced or unless with permission
of a game official.
g. Refusing to comply with a game official’s request.
h. Using tobacco or smokeless tobacco.
ART. 2 . . . When the ball becomes dead in possession of a player, he shall not:
a. Intentionally kick the ball.
b. Spike the ball into the ground.
c. Throw the ball high into the air or from the field of play or end zone.
d. Intentionally fail to place the ball on the ground or immediately return it to a nearby
official.
PENALTY: Unsportsmanlike conduct (Arts. 1, 2) – (S27) – (S7-27) – if dead ball, 15 yards. Also
disqualification if flagrant – (S47). In Article 1a, the player must remove the offending item
before he is allowed to participate. The second unsportsmanlike foul results in disqualification.
(See 9-8 PENALTY)

That would be a foul by B. The OP was asking about a foul by A.

I can't think of one. Team A is allowed to call signals, they don't say who is allowed to call signals.

There's the old voice inflection by the QB but that's nothing.

There's the QB head bob or hand shake but there again that would be ruled a false start.