touch dimmer table lamp

[Jules]

I have been given one of these to repair. Mains plug, 60 Watt bulb. The capacitative switch doesn't work. The metal base can be touched anywhere to activate the switch. One touch turns the light on dimly, second touch brighter, third touch max brightness, fourth touch off. The circuit box inside the base has been filled with an annoying "tamper-proof" black substance inside covering all the components, and effectively sealing them and preventing removal. I can't read the IC or semiconductor numbers! There is an 8 pin DIL chip (555 timer or 741 opamp?), and a TO220 style 3 pin semi with metal heat sink (MOSFET or TRIAC ?) plus a few other caps and res. The fuse is OK. Has anyone repaired one of these, or knows the likely fault. What are the IC and semi numbers?

 

[Nilo]

I already built a touch dimmer using a dedicated IC S566B by siemens. Example scheme below.
This one is more complete that what you're saying. One touch turn ON, keep touching will increase the power slowly until you take your finger off. If you keep touching it will get the max peak and then will start going down until the minimum and then going up again, kinda slow cycle. Another touch and turns OFF. When turns back ON again, output the same power that the one when was turned OFF. Works pretty good.

Nilo