Henni,
this is from the PA50SD manual.
SUPPORTED CARDS
You can use the following types of cards to save or load data
to and from the Pa50SD’s internal memory:
• SD (High Speed, Ultra II, SDHC)
• MMC
• MicroSD with an SD adapter
• MiniSD with an SD adapter
Note: Before you can use the SD/MMC card, you must format it on
the Pa50SD. Don’t use your computer or digital camera to format
(initialize) a card you plan to use with the Pa50SD. If the card was
formatted on a different device, it may not work correctly with the
Pa50SD
Note: The SD/MMC card is not included. It must be purchased
separately.
Note: The Pa50SD supports SD cards with a power supply voltage
of 2.7–3.6V"

Hope it helps.

Deane