The OEM750X-M2 is a very good possibility for replacing the PDX. They have the same basic indexer, but there are a few software and hardware differences:
POWER SUPPLY: The PDX took 110 and 240 Volts AC input. The OEM750X requires an external 24 - 75 VDC power supply.
BUS VOLTAGE: This directly affects the speed capability of the motor. The PDX's bus voltage was 70 VDC. The OEM750X's bus voltage depends on the DC voltage being put into it; whatever DC voltage is put in is the bus voltage for the OEM750X. Using a different power supply that only puts 24 VDC into the OEM750X will make the OEM750X provide much LESS performance than the PDX could.
MEMORY: The PDX retained its memory on a power cycle. The OEM750X requires the -M2 option for this same functionality.
MOTOR RESOLUTION COMMAND: The PDX had a MRD command. The OEM750X uses MR. (MR also worked in the PDX but was undocumented.)
MOTOR RESOLUTION SETTING: The PDX had a default and maximum drive resolution of 4,000 steps/revolution. The OEM750X doesn't have that 4,000 setting. It does have 2,000 and 5,000. The distance would need to be changed to account for this. The acceleration and velocity don't need to be changed because they are already scaled to revolutions.
An example of an existing program that turns the motor two revolutions would be...
PDX: A10 V5 D8000 G
OEM750X: A10 V5 D10000 G
16 Nov 2016 removed PS300 and PS1000 listing because obs nc