Joker Radio Club has been in the air in many QTHs in Finland.  The club was established to activate different amateur radio activities.
Our club calls are:
OH2J, OH2AAJ and OH6AAW
OH2-000 SWL call

We have been in the air as:
OH0AAJ, OH0AAW, OH1AAJ, OH1AAW, OH2AAJ, OH2AAW, OH3AAJ, OH3AAW, OH5AAJ, OH5AAW,OH6AAJ, OH6AAW, OH8AAJ and OH8AAW.
Also we have used special prefixes OF, OG, OI and OJ with most of our call signs.
And of course also /-call signs have been in the air, like OH2AAJ/5 and OH2J/6.
Earlier we had in Finland nine call areas and Åland island OH0 and Market Reef OJ0.Several years we just changed the number in the call sign to show where
we were operating. Now we have on one call area which is the whole Finland without OH0. The number can be from 1 to 9,
but it is allowed to use also old call areas in the end of the call, so that You can show in which part of the country You are operating. Like OH2AAJ/6.

And during the year 2000, we sent SWL reports from OG2-000 and OH2-000. 
There was in the air also the call sign OH2OOO,
but that belongs to the club of Valkeakoski OH3AB.