I have not had the encoder which is behaving strangely apart, but I have had another one apart.  The wheel has windows in it, not stripes.  It has a rather large gear increase between the input and the chopperwheel...like I'd guess 50:1 or maybe more. 

My box has no serial and has a place for a 9v battery.  

I assumed a rev G would be later then a rev B....which proves what they say about 'assume.'

I will tell him to hold the self=test key instead of the CE key.  I really do not think this is the problem, though.  

What is a 'normal' range for a cal number to get the console to be reading at a click per second or so?  These require what I consider very high numbers....9000 or thereabouts...in order to get the rate down low enough that you can run a 'load' without resetting the empty alarm several times.  

I will interchange the sensors as soon as I get a chance.  For now, the rig needs to be running, though.    I probably need to just order some Raven encoders. 

Thank you very much for your answers, Ted.  You are an invaluable asset to this board when it comes to Raven!