The dimmers in this section are part of the equipment collection 
of the lighting archives.  The collection ranges from outdated 
assembly-line products prototypes to unique approaches to 
specialized problems in contempoary theatre.  Afile of material 
relevant to each acquisition has been assembled.  These contain 
(if avaiable) catalog information, photos, patents, drawings, and 
recollections of the equipment by persons involved in its initial 
devlpoment.

I-14D01   SLIDER RESISTANCE DIMMER ROAD BOARD--Five Dimmers.  An early 
          Kliegl rental unit,  ca. 1910.  Steel case with rubber-tired 
          casters,  knife switches,receptacles for two half-plugs each
          dimmer, worklight outlet.
          Donated by Kliegl Bros. (Joel Rubin).


I-14D02   CUTLER-HAMMER NON-INTERLOCKING CIRCULAR PLATE RESISTANCE DIMMER
          66Ow 5.7A 115V, No. 11311 H4.
          Donated by PSU Theatre Arts Department.


I-14D03   WARD LEONARD 400w 33A AUTRASTAT DIMMER
          Non-interlocking rectangular type.
          Donated by PSU Theatre Arts Department (1972).


I-14D04   WARD LEONARD No. 2766 VITROHM NON-INTERLOCKING DIMMER
          Type 71-112, 2705-3000w 115V, s.o. No. 5655220.
          Donated by Century-Strand (1972).


I-14D05   SUPERIOR LUXTROL TMR 12KW MAGNETIC AMPLIFIER DIMMER
          Type P12, 120V 60c, ser. 109.
          Donated by Century-Strand (1971).


I-14D06   GENERAL ELECTRIC THYRATRON TUBE CONTROLLED SATURABLE REACTOR 
          DIMMER BANK
          An incomplete system:  two reactors and a tube panel.
          Donated by Shelly Electric Company,Philadelphia through the
          efforts of Joseph L.Vetter (1975).
 

I-14D07   THYRATRON TUBE DIMMERS
          Designed and built by George Izenour, 1950, for Carnegie 
          Institute of Technology.  One of four prototype systems, the 
          others installed at the Yale Drama School, the Goodman Theatre 
          in Chicago, and at a theatre in Delaware.  This design 
          represents the first use of the back-to-back circuit for remote
          electronic dimming of AC current, and the first use of plug-in 
          dimmer chassis for ease of maintenance and repair.  Control 
          current is AC.  The front end of the system is also in the 
          archives, No. C2.
          Donated by Carnegie-Mellon University (1972).


I-14D08   THYRATRON TUBES
          Three steel-jacketed National Electric power tubes. NL-732SF, 
          NL-733 (used in C-I 6kw dimmers ca. 1960), NL-1006 (used in C-I 
          12kw dimmers ca. 1960).
          Donated by George Izenour (1976).


I-14D09   XATRON TUBE
          Specially fabricated by Electrons, Inc. for G. Izenour, ca. 
          1955.  Although the original Yale system included six 20kw 
          thyratron dimmers, Izenour reports that sizes over 10kw were 
          never sufficiently reliable.  Half-cycles would occasionally 
          drop out, causing a flicker in the controlled lamp on stage.  
          These tubes were to be paired in place of thyratrons to create
          dimmers up to 50kw. Ignition problems were never solved.
          Donated by George Izenour (1976).


I-14D10   THYRATRON DIMMER MAGNETIC RESET "SHOE BOX" CONTROL
          G. Izenour design, ca. 1955-56.  This plug-in box comprised the 
          firing circuit for an improved thyratron dimmer.  It was 
          mounted on one side of the dimmer rack, the thyratron tubes on 
          the other, with the filtering circuitry located on the framework 
          between.  The "shoe box" includes simple adjustments for 
          trimming the dimmer by centering the output curve and setting 
          minimum and maximum cut-offs.
          Donated by George Izenour (1976).


I-14D11   CENTURY No. 2905 "TOMATO CAN" SCR DIMMER
          Cylindrical-shape plug-in design, ca. 1959-60.
          Donated by George Izenour (1976).


I-14D12   CENTURY CCR DIMMERS
          Display rack of six plug-in SCR dimmer designs, 3kw to 12kw, 
          ca. l960 (200 series) to ca. 1970 (300 series).
          Donated by George Izenour (1976).


I-14D13   SICODIM MODEL 302 SCR DIMMERS
          60Hz 120V 3000w.  Rack of twelve plug-in dimmers, part of a 
          Century/Sicodim Memo-Q demonstrator unit (Archives No. C5).
          Donated by Century-Strand (1973).


I-14D14   METROPOLITAN ELECTRIC CO., NEW YORK, NY
          SCR Dimmer Chassis (ca. 1959), Model No. 55, with Magnetic 
          Amplifier front end.
          Donated by Terry Wells, of Skirpan Lighting Control Corp., (1979).


I-14D15   WARD LEONARD VITROHM Dimmer Assemblies,
          (3 sets:  Two type P-25, one type 72-P27)
          Donated by Sanford Nicol of the Ogontz Campus, Pennsylvania 
          State University (1979).


I-14D16   CENTURY LIGHTING, INC. EDKOTRON DIMMER COMPONENTS
          One dimmer unit No. 260, comprising six 1.8 kw SCR dimmers, One 
          control unit No. 261 & one control cable.  Part of a system used 
          for Artists Series events in Schwab Auditorium, Penn State 
          University.  These units were the first production run released 
          for sale by Century Lighting, Inc. (1964)
          Donated by University Auditorium Services, Penn State Univ. (1979).

For more information about the archive's Web site, contact Corey Felgenhour by voice mail at (814) 863-2892 or at felgenho@psu.edu.

For further information about the archives, contact:
William Kenyon
Director, Stage Lighting Archives
The Pennsylvania State University
510 Academic Activities Building
University Park, PA 16802
(814) 865-2261