The H-5 searchlight signal was a significant departure from earlier styles.  The changes increased the serviceability of these signals.  While the changes were significant, the fundamental manner in which the signal operated remained the same.

As shown in the photograph below, major changes included the addition of terminal blocks on the inner sides of the housing with connectors to the internal unit.  This combined with the separation of the light unit from the internal unit and the addition of a lever mechanism for securing the unit in the housing made servicing easier.  To remove the internal unit, the light unit is unsnapped and hung on the back door bracket.  Next, the metal bar across the connectors is rotated 90 degrees allowing the connectors to be pulled loose.  After this, the mechanism is removed by moving the lever below the unit to the left, lifting the rear of the unit and pulling it straight out.  The major advantage in this design is not having to detach any wires - just two connectors.  This also eliminates the possibility of not properly reconnecting the wires to the terminals.

Above. View of H-5 signal with the light unit and electrical connectors removed from the internal unit.  The electrical connectors grab connecting pins located on the top rear of the internal unit.  While difficult to see, a rotating metal bar located between the sets of pins holds the connectors in place when the unit is in service.  To lock the connectors, it is rotated 90 degrees.  The light unit is wired directly to the side terminals and would not be removed when the internal unit is removed for servicing.\

Right.  View with the internal unit and light unit removed.  Note that the inner doublet lens is an integral part of the searchlight housing and not part of the internal unit as on the H-2 style signal.

Above.  Rear view of the H-5 signal showing its characteristic right swinging door with protruding section at the bottom.

Above.  H-5 signal with rear door open.  Note how the rear door covers the outside edge of the gasket providing the gasket with protection from the elements.  On the H and H-2 style signals, one side of the gasket is completely exposed to the elements.  While difficult to see, there is a metal bracket on the inside of the door for hanging the light unit when it is removed from the internal unit.

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