A main signal and a distant signal of the
<a href="http://www-users.rwth-aachen.de/christoph.schmitz2/smsignal.html">semaphore
system</a> showing Hp0 (stop) and Vr0 (expect stop) in Aachen Rothe-Erde on 13
July 2001. D 423 (Oostende-Cologne) has just passed. Note that the distant
signal is at reduced distance to the next main signal, for that a triangle is
placed on it's post plate.
<p>
Digital photo by
<a href="http://www-users.rwth-aachen.de/christoph.schmitz2/index.html">Christoph Schmitz</a>