GSM test sets (HP 8922M, for instance..)

[John Case]

There are a lot of HP/Agilent 8922M units for sale very cheap (less than 
US $500).

I know that these devices can simulate a GSM base station, but does that 
simulation occur over the air, or do I need to connect my handset I am 
testing to the 8922M with a cable ?

I know I need to get a 8322A expansion for the unit - any other details I 
should look out for ?

Also, what is an equivalent test unit for WCDMA (3g) base station 
simulation (I know these will be more expensive).

Thanks.