Detecting digital signals?

[Alex Noble]

Sorry, but this isn't a strictly synth-diy issue, more a general
electronics one, but anyway - I've got a couple of contacts on my awe64
value soundcard, which are documented (but unsupported) as spdif output,
however, to be able to realistically use them I need to fit some kind of
connector. I'm sure this won't do my warranty any favours, so I want to
check if there's actually a digital signal present before I go on a
soldering spree (only the 64 GOLD has a supported digital output)... I
don't know enough about the nature of electronics to be able to find out
how to detect such signals, so I was wondering if any of you helpful
knowledgable people would help me find a way (or even - if anybody knows
anything about the card - tell me if the spdif output really works).
Thing is, I haven't really got any decent test equipment (none which is
really suitable, I think), just a bundle of misc parts, and a tasty old
avometer. Is it feasible to use these tools to try and find the signal,
or should I try a different direction?

Thanks in advance!

Alex Noble.........................................alex at elbon.demon.co.uk
  Wicked original music for your ears: http://www.elbon.demon.co.uk/es/
                     Home of Euphy Scott Productions.