It sounds like a Melico enlarging meter/timer I have. There may be the timer built in or, the time dial may indicate the time that should be set on a separate timer.
Your enlarger I believe needs VC filters if you want to print on variable contrast b&w paper. The notes you found in the meter box appears to suggest it was used with a dichroic enlarger head, which I am pretty sure you do not have.
Make a test print that has a good tonal range from white to black, at an aperture setting that allows the time to fall at somewhere around 10-20 seconds.
Then, without changing the enlarger head height, or aperture, and with all lights off, place the probe on the projected image of the negative for which you just made the good test print.
Select an in an area where there is the first hint of grey away from pure white. There are other ways of metering a scene, but use this one for now.
If you used a VC fitler, take it out, and meter just white light; it is likely that the meter is old enough to not be uniformly sensitive to all light colours the filters can put onto it.
Set the meter time dial to match the time you exposed the test print at.
Then set the paper sens(itivity) dial to 'balance the bridge' This may be the point on the dial when the + and - lights are both lit, or both extinguished.
Make note of this paper sens and the developer dilution and development time that was used with it. I use yellow 'post its' on the box, and a pencil; easy to read under safelight illumination.
Want to make a bigger enlargement? - move the head up.
Without touching the paper sensitivity, meter the areas where you want first hint of white, and adjust the time dial until the bridge balances. Safelight illumination can throw these readings off.
Then put your VC filter in, set your timer to match the desired time (you could adjust the lens aperture to get a time between 3 and 50 seconds). You will get the same tone without a new test strip.
It can even be used to measure contrast ranges of negatives.
Meter the thinnest part of the neg that you want tone to read in the shadows. Set the time dial to 3, and then adjust paper sens until the bidge balances.
Now set the probe on the densest part where you want slight grey. Without touching the paper sens adjust time until you balance. That will give you a measure of the contrast range.
It wont be as powerful as some analysers, because it has limited range of 3-50, and appears to be a linear scale;
3 sec is the base measurement
6 sec is 1 stop more, or +0.3 logD
12 sec is 2 stops more, or +0.6 logD
24 sec is 3 stops more, or +0.9 logD
48 sec is 4 stops more, or +1.2 logD.
Most 35 negatives aim for delta log D of between 1, and 1.5, when they are developed, so you run out of scale with just '4 stops' of tiem available to you.
Look to the tables of paper speed and contrast range on the ilford data sheet include with MGIV and you will find this information,(but expressed mulitplied by 100), to tell you want range in a negative a given VC filter will print to show details between all white and all black.