My first 30m WSPR experiments with a strange call showing up

Last saturday night my computer has been running all night long the WSPR (whisper) software from ….. to see if I could receive that mode too. My wife had the night shift in the hospital and could not argue that the computer is making too much noise in the bedroom 🙂 That is the downside of having the shack in the bedroom.
I set the receiver to 10.138.7 in the 30m band and went to bed.

Sunday morning I noticed two calls on my screen : IK1RKU and ZX5PIZ. The first one seems a common user on the band according the WSPR network on

But the other call is strange. What country is ZX5 ? I couldn’t find a matching country.
I entered the locator on the site of F6FVY to see where it is. This locator is located in the South of Greenland and callsigns in Greenland would start with OX, so could it be OX5PIZ ?

Searching in Google to OX5PIZ or ZX5PIZ showed no results. And the MEPTspots database also found nothing.
False decoding I assume, but for a moment I hoped that it was a real callsign 🙂

Today I  fired WSPR up again to see what is passing by. At the moment of this post it is K1JT (the creator of WSPR) and HA5CVZ. And my receiver has a drift 😉