It can be emulated with a netlist (discrete sound) if all components/values are known.

sean: Do you know the R/C values for Big Trak? The schematics online say R=83K, C=100pf, which would imply around 125kHz. But comparing it to YouTube vids, it should be around 200kHz.

The Coleco Football game is also too slow with R=39K, C=100pf. If I had to guess, I'd pick R=30K... orange-black-orange instead of orange-white-orange, hmmmm big difference in contrast.