Help with Arkanoid spinner

[telengard]

I'm trying to get an arkanoid spinner working (using it with an Opti-PAC so wasn't sure if the general forum or this one was more appropriate).

As received from eBay it did not work.  Found this site:

http://www.zumbrovalley.net/readpost.php?artid=1

and following the advise there I ordered some replacement optical encoders which were mentioned were most likely drop in replacements:

http://www.optekinc.com/datasheets/OPB859.pdf

I've pinned out everything to make sure I have it right and I'm pretty sure that part is OK.  What I'm seeing is the output at the receivers (pins 1 and 4) is always @ 5V.  When moving the wheel I never see it dip to 0v.

Any tips on things to check or ideas?  As I mentioned I've pinned everything out following the schematics at the above page and also verified (out of circuit) that the 2 resistors are 150ohm (in circuit the resistance goes way up which surprised me, I would have thought they'd stay fixed and current/voltage drop would change).  I also only have the 2 150 ohm resistors on my board and from what I've read, the other 2 aren't needed.

~telengard