Measuring caps

I bought a B&K/Dynascan 820 capacitance meter on eBay. I have no experience in using a cap meter and this one came with no manual. Anyway , when I plug in a cap marked 33 microF, 35VAC the display flashes a diferent figure maybe twice a second between 0.033 and 0.042 fairly randomly. Actually it seems to step from highest to lowest value. Is it how it is supposed to act? and if yes, which value is the right one? Lowest, highest, average?
The cap is a eletrolitic Inter Technik it is meant to go in a crossover.
 
Have you contacted the company about a manual?
Some companies (Tektronix comes to mind) have places on their websites where you can access/order manuals, so you might try their (hypothetical) website.
Whilst we're on the subject of test gear, I have one of their freq. generators, but have never been happy with it. I'm open to suggestions as to good test equipment. Want to widen this out to include more than cap meters? (Which is something else I wouldn't mind buying, actually.)
For what it's worth, I give the Fluke 8060A a five star rating. Expensive, but worth it.

Grey