On 22/05/2019 16:54, The Natural Philosopher wrote:
On 22/05/2019 14:23, petek wrote:
On Wednesday, May 22, 2019 at 1:50:40 PM UTC+1, wrote:
On Wednesday, 22 May 2019 12:57:35 UTC+1, petekÂ* wrote:

I have a floor standing lamp which has a touch sensitive switch. If
you touch the lamp housing or upper part of the stem the lamp
toggles through 2 or 3 brightness levels and on/off. It hasn't been
used for some time but when I tried it the other day it is not
working, i.e. it won't switch on. I've changed the bulb but still no
joy. Any ideas what the problem is, and if it is repairable? TIA
Pete

If you don't know what the problem is you don't know how to repair
it. Have you checked the obvious stuff, fuse, screwed connections
etc? If the touch controller is fried it may be bypassable.


NT

Yes, I've checked all the obvious stuff. My question about it being
repairable could have been stated better. I don't know how these touch
sensitive lamps work so I'm assuming there is some internal gismo
(touch controller?) that is not functioning. If so, would it be a
generic unit that is replaceable or would it be unique to the brand of
lamp?

in general you can pick up hum from any metal connecteed to a human...
When I designed a similar circuit we had a cmos chip behind it to boost
and latch te signal

My giues is there si either a custom chip or a standard CMOS chip
inistde. If its custom bin it.

Bin the control and either fit a physical switch to bridge them or link
the wires and fit a switch in the lead from the plug to the lamp.

SteveW