Does Panasonic DP-ub820 have universal power supply

Why not go to https://www.panasonic.com and enter the model number to look up the specifications? :-)

Actually no, as the Panasonic players have a suffix on each model which indicates the power it accepts as well as region of blu-rays and DVDs it can play. The cousin of the DP-UB420 is the DP-UB420P-K, which is 110 v, 60 hz, but NOT compatible with europe or Britain nor anything outside of region A (North America) blu rays. This is likely true of the DP-UB820 as well. They do NOT make a universal blu-ray as yet I am aware of, though who knows what may have been brought out this year. However, each manufacturer likes to keep their products regionalized and marketed within each country. so this is likely still the case. The DP-UB420GNK is a 220 v 50 hz product, but while it only works with region A blu-rays and class 2 DVDs, has Australian marketing and needs a plug adapter. It can be used elsewhere but the blu-ray region it plays is still A!

Contact Panasonic for anything further, though good luck! I learned this much by mistake and further education might only come with much time and effort. They keep their marketing distinct and separated, and crossing country boundaries can be very challenging!