PET 2001-8 Repair: Bug in Schematic?

[NivagSwerdna]

I've just bought a non-working Commodore PET 2001-8 

Looking at the schematics.... http://www.zimmers.net/anonftp/pub/cbm/schematics/computers/pet/2001/320008-2.gif

I'm trying to work out the decoding for RAM chips I2 and J2.... I think there might be an error on the schematic... specifically I think pin20 of both I2 and J2 should be nBA10?

If anyone is familiar with this bit of vintage tech I would appreciate a suggestion as to a forum where I could ask my question.

Thanks in advance

[Andy Watson]

I can't see a source for nBD10 on the diagram - pretty sure it's a typo. J2 is labelled correctly. Pin 20 is a positive chip-select - I would expect a positve/true BA10 to select for the range 400-7ff.

[NivagSwerdna]

I'm now 99.999% sure it should be BA10. 

Thanks