Maintaining compatibility between Cassini systems requires a basic understanding of compatible models. Test Instrument Modules (TIMs) contain multiple software "Instruments", that may share a common hardware model number. Software Instrument descriptions include a model number as part of it's description, but that should NOT be used to identify compatibility. ONLY when comparing hardware TIM model numbers can compatibility be assured.
Roos Instruments attempts to maintain consistency when on Quotes, Shipping documents, and Internal software designations. However, software definitions may differ to maintain compatibility in Test Plans. Model numbers are used to distinguish TIMs. Different model numbers may expose identical, 100% backward compatible functional instruments to the system.
Only "8533" is significant when identifying compatible hardware.
Internally, the 7th digit, alphabetical digit (A) represents the hardware revision of this model. Revisions are made when there are internal hardware changes. 100% compatibility is always assured. The 8th digit (1) is usually not present on any identifying labels or documents, but represents the firmware revision for a particular hardware revision. Since the firmware is updated automatically as part of normal software operations and is managed by Patch level and the Cassini ShortCut, it would indicate a update Short Cut is required.
New model numbers may be 100% backward compatible with a specific model after it has been discontinued or replaced.
The Receiver instrument, RI8587A is compatible with RI8581A (but not vice versa).