Mainboard-listed ISDN Holdings, the integrated engineering solutions provider, says 2Q09 sales slid 27.1% to $23.6 million from $32.4 million as demand fell in the global economic downturn.

Motion control remained as the biggest revenue earner among the three key business segments in the second quarter. It raked in sales of $17.4 million, equivalent to 73.8% of group sales, followed by Other Specialised Engineering Solutions at $5.5 million.