Help w/ II+ video

[markd@pravda.cc.gatech.edu (Mark Devaney)]

Hi - I just grabbed an Apple II+ from a thrift store and am having
some problems getting it working (probably why it ended up there in
the first place).  Anyway, the power comes on but I'm not getting any video - 
I'm plugging into the back video port, there's also some sort of RF converter
inside the box w/ two RCA outputs but they don't work either.  I'm not much of
an Apple expert, just wondering if there was/is some common problem w/ II+
video I should look at first.  
Thanks
Mark
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 Mark Devaney                    "Mister Order, he runs at a very good pace 
 Georgia Institute of Technology  But old Mother Chaos is winning the race"
 markd@cc.gatech.edu                   _The Illuminatus! Trilogy_           
 http://www.cc.gatech.edu/ai/students/markd/
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