= Finite pulse count for a falling Schwarzschild beacon
{title2=$N=\left\lceil(s_H-\delta)/P\right\rceil$}
A freely falling source emits <optical pulses> at proper times $\delta+nP$, for integers $n\ge0$. If its horizon-crossing <proper time> is finite, only pulses beginning before $s_H$ can escape. Their number is the displayed ceiling, for $0\le\delta<P<s_H$. Infinite <Schwarzschild time> at crossing does not give infinitely many emitted pulses. The pulse phase $\delta$ fixes both the count and the redshift of the last pulse. If a finite pulse straddles the horizon, its exterior portion has an arbitrarily late, increasingly redshifted received tail.
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