"jss" wrote in news:1168804333.132680.125310
@m58g2000cwm.googlegroups.com:

Hi all,
My laptop lcd was becoming pink at power-on during a couple of minutes.

So I looked in ebay and bought a similar tube, 2mm thick by 305 mm
long. Replaced the tube to find that the inverter fuse blew. Replaced
it with a calibrated wire from a bigger fuse and everything seemed fine
apart a bit more heat which is tolerable by me once that this is an old
laptop close to its life limit.

Then I tried to operate the laptop on batteries just to find that the
inverter shuts off after a little while. After a thought I guessed that
by reducing the input voltage to the inverter, which happens when it is
operated on batterires, the input current rises once that the output
power is constant. So the conclusion is that it must be close to the
power handling limit. Not difficult to admit once that I had to raise
the fuse caliper.

As working only on AC is not acceptable, I decide to invest a bit more
time and measured the current of both the old and new lamps to be 6 and
13 mA. All the specifications that I could find for this inverter
states 6 mA at maximum brilliance, which is correct for the old bulb.
Tried to measure the voltage under load (bulb lit) but this is a bit
tricky although I have a good Fluke multimeter although not equiped
with High Voltage probe. Anyway, the measured voltage is about the same
with both bulbs, about 450 Vrms.

So, after all this, it's apparent that the new bulb consumes about
twice the power for the same light output, any comments on this and how
to overcome it in order to have my laptop working on battery also?

Eh, you just bought the wrong tube. Easiest to throw it away and buy the
right one. Look at a site such as

http://www.lcdpart.com/doc/ccfl.html