ET-1 Enlarger Timer
- Easy-to-read, linear dial scale--front-panel calibrate control.
- Compact plastic case resists photographic chemicals.
- Handles up to 350 watts at enlarger or safelight receptacles.
- Timer does not have to be reset after each cycle.
- All-electronic circuit for greater accuracy.
The model ET-1 is an easy-to-build electronic device to be used by amateur or professional photographers in timing enlarger operations.
The calibrated dial on the timer covers 0 to 1 miniute, in five-second graduations. The continuously variable control allows setting of the "on" cycle of your enlarger, which is plugged into a receptacle on the front panel of the ET-1. A "safe" light can also be plugged in so that it is automatically turned "on" when the enlarger is turned "off". An internal relay handles up to 350 watts at enlarger or safe light receptacles.
The all-electronic timing cycle assures maximum accuracy. To start the timing cycle the timer dial is first set to the desired number of seconds and the spring-return lever seitched to "print". The timer does not have to be reset after each cycle, merely flip the switch to print, to repeat the timing cycle. When the lever switch is moved in the opposite direction to the focus position the enlarger will remain "on" for focusing and masking. A control is provided for the initial calibration so that the timing cycle will correlate with the panel calibration. The ET-1 requires only 3 watts for operation so very little heat is generated. This results in long life of the components and no undue heating of small dark rooms. Once the timing cycle is started, the operator is free to do "dodging" or process already-exposed prints without fear of over-exposure. The timer is housed in a compact plastic case that will resist attack of photographic chemicals. Its small size enables it to be placed almost anywhere at the enlarging position. Top-quality components are used throughout to insure many years of troublefree performance. This timer can be built in just one evening.
Specifications: Timing range... 0-1 minute, continuously variable. Controls... Off-On/Timing, Focus/Print, Calibration. Receptacles... Enlarger and Safelight 350 watts maximum each. Tube... 1-6D4. Power Requirements... 105-125 V 50-60 Cycle AC, 3 watts. Cabinet Size... 6¼" long, 3¾" wide x 2" deep. Non-corrosive plastic. Construction time... 1 evening.