Yesterday I wired in a new turnout to one of my existing K83 decoders. The red output switched the 74491 actuator successfully, but the green did nothing. Since I had already shorted out the micro switches in the actuator I was pretty sure that it was not the actuator. However, while I was checking for a loose connection I got the distinct smell of burning electronics and the magical smoke release at the actuator. So I checked the outputs of the K83 and sure enough I had a short between brown and the affected green output. So I assume the K83 caused the actuator to fry and not the other way around.

Opening the K83 shows no burn marks but I assume the output SMD device Zetex ZDS1002 has failed. Has anyone replaced one of these 8 pin SMD devices? if so, how difficult was it to remove the defective unit with its 8 solder connections? Also where did you get a replacement ZDS1002 from?

An Internet search shows a ZDS1002 available for a price that appears to be higher than a good used K83. So it probably isn't worth it.

If one side of the ZDS1002 has failed, what is the possibility of the other output failing as well? I was thinking of using the red output for a single solenoid device such as an uncoupler, but I don't want to burn out any more devices.

Cheers
Peter

I have tried to repair k83's in the past by cannibalising what I thought were good bits from failed units to repair others. However I have never had any success so I don't bother now. As you have said, a good used k83 is not that expensive so I just buy a replacement.

My K83 is a Marklin 6083 with the SMD components, but still with the old style banana plug connections.