There's a bit about the Northern Hammond here, Cassp.
http://zk3.hammondforum.com/archives/1997.03.march/msg00486.html

I'm pretty sure the one I played, did not have harmonic percussion...I believe my friend Ray, added it, with some kind of kit.
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Yamaha Tyros4, Yamaha MS-60S Powered Monitors(2), Yamaha CS-01, Yamaha TQ-5, Yamaha PSR-S775.