Whilst looking for something which I put in a safe place in my stocks(no. I didn't find it!). I found that somewhere in the past few years I had purchased a small dome CCTV camera. As one of my cameras was very old and not very sensitive, I decided to fit the dome camera in it's place. The theory was OK, but I found that the camera had interference patterning and vertical blooming when operating. I checked the operating voltage, it was a bit high, so hooked the unit up to my bench psu to see if this had any effect. No, over a range of 9 to 15V the behaviour was the same. Then by accident, I switched off the study lights and found that the interference patterning was apparently being caused by the CFLs radiating into the unscreened camera. Subsequent testing didn't remove all the vertical blooming effects, so I'm still looking into that. I replaced the old camera with a spare modern metal cased outdoor unit which I had in my stocks and it all worked OK. It appears that some plastic cased cameras can pick up radiated interference from CFLs and fluorescent lamps. Anybody else found this?
The PSUs required came from my stocks of it may be useful one day items!