[sdiy] AD734 uses?

[Thomas Hudson]

I'm in the process of cleaning up my bench and parts stash and came  
across four AD734AN "10 MHz 4-Quadrant Multiplier/Divider" chips. The  
transfer function is [(X1–X2)(Y1–Y2)/U] + Z2.

I have absolute no idea why I have these, but I was wondering if  
anyone has used them for synth or fx stuff. Seems like they might be  
good for a balanced modulator or some other fun stuff.

Tomy