Desk light problem

[MattF]

Just wondering why do these florescent dest lamps need a chunky solid transformer/ballast, and a 230v florescent low energy bulb runs on a circuit board as big as a postage stamp?

They're a one shot deal. Reliability isn't as important, as you don't replace the lamp when it blows. The board is renewed with each bulb, unlike a strip or desk top lamp. Resoldering the board and heatsinking the thing would probably make those little units more reliable out of their enclosure, as they do tend to suffer heat problems when they're in the bulb unit, (not surprising seeing as they're enclosed with inadequate heatsinking). Most of the bulb failures I've had have been down to the board and not the lamp.

Anyhows, back to the original bit, post a photo of the one you've disassembled. No idea what they're like offhand, and being a Tyke, I'm way too tight to disassemble a working bulb to look.

 

[gordon stephenson]

New light arrived this morning,!!Found it propped up against my front door. Went inside and found a card thro' the letterbox,saying the light was leaning on the door!!!Bought the model that takes a normal bulb and has a magnifying lens, However the plastic swivel on the head was snapped, Phoned seller and he is sending out another on monday.

 

[gordon stephenson]

Here you go MattF,
The 2 pairs of electrodes had a fine filament ,one filament to go in each end of the light tube.