use of Gralab 300 timer

Hi,

<p>I recently purchased Gralab 300 darkroom timer (second hand).

It didn't include any manual, so no I am bit confused with all the switches.

<p>Could someone explain how this thing works. I will probably use it mainly for

film developing. Ofcourse it would help a lot if user's guide would be available

somewhere on the net. But Google didn't help much :/

Plug your safelight into the safelight outlet. Plug your enlarger light plug (some enlargers/light sources have a separate plug for this) into the enlarger outlet. Turn your enlarger on (also any switching that is required to normally have power running to the enlarger light) with the time switch to the on position and the focus/time switch to the time position. Now, when you switch to focus position on the upper left switch, the enlarger lamp will light and you will be able to focus. Turn back to the time position and set the countdown hand(s) to the time you desire. When you switch the upper right switch to on, it will trip the timer, turn on the enlarger light, shut off the safelight and then turn off the enlarger at the end of the time you set and also turn the safelight on again.

It soon becomes a very natural sequence and intuitive. This all works best with a safelight that goes on and off quickly (vs a sodium vapor or similar type that require ramping up).

I don't use the 300 for enlarging, but it is perfect for film processing.

The switch at the upper left corner should be set to "Time".

The larger hand is for minutes. The smaller one is for seconds. Move them clockwise to set your time. For 5 1/2 minutes the minute hand is moved to 5, and the second hand to 30. When setting the time, the switch in the upper right corner should be in the off position. When you are ready to start the timer, toggle the switch to the on position.

You can set the hands when the switch is on, and the timing will start immediately, but doing it that way might eventually cause problems with the timer mechanism.

The switch in the lower right corner is for a very loud buzzer that will alert you that the timing is over.