CF-28 backlight mod

Hi everyone,

My CF-28 screen is very dim. I can see the inverter is fine. It's an old laptop, of course, and it appears the CCFL backlight is worn, tired, and needs replacing.

I've found a company in the UK that sells replacement backlights ( http://www.laptopsockets.co.uk/), they're a cheap part (but there's a lot of labour needed to fit one properly), and I need to know 2 pieces of information, the diameter and the length of the tube. Rather than opening up my screens (I have a 12.1 and a 13 inch screen I'm playing with) and measuring with calipers, does anyone know what the correct sizes are for these cold cathode tubes? That should save me loads of time, and make this more generally available to those of you who might want to try it out for yourself.

One other thing. Is there a way of getting an even brighter backlight? Just a thought. I was wondering if I might get away with a slightly larger diameter backlight, or use some other alternative.

And finally, I didn't see anything in the main FAQ about this. There must be loads of people want to do this type of mod.

Cheers,
A

 

HI: Wouldn't it be easier just to buy a new screen off eBay? They are available. Spark

 

Backlights aren't too hard to replace if you know how to do it... I've replaced lots of backlights in my time and about 40% of the time i get them they are damaged from shipping because they are so **** fragile... I only buy from a few particular vendors because I know that they know how to package them... now if you don't know how to do it, yes it would be MUCH EASIER to just replace the whole screen...

 

NEW LCD for a CF-28?

*SNARF*

Few and far between, my friend. And d@mn pricey when they DO show up.

mnem
Here come those dear sweet indians again!

 

A - I've posted quite a bit on my experience in this particular bit of service; do a search in the forum for " mnem ccfl " and you'll see most of what I've posted.

I don't know the correct dimensions of the particular tube you're looking for; but I have done more than a few and can offer some insights.

First -

I usually COUNT on having my machine down for at least a week or so... the nature of this job is that you HAVE to disassemble the LCD, remove the CCFL, measure, order, and wait. Even if someone here HAD done the job before, there's no guarantee that the LCD YOU HAVE is the same model; in fact, sometimes even the same part number will have a different CCFL tube than previous or later parts, or in some cases might even be made by a different MFR altogether.:confused2:

What you need to do is disassemble the unit (trying to avoid separating the layers of the LCD as much as possible to prevent dust inclusion) remove the CCFL, then stuff it all in a garbage bad & seal it up. Get your measurements, then go to Digi-Key & find the nearest SMALLER size tube they have. Remember to allow a few MM for longer solder pegs on the tubes. :GEEK:

Most of the LCDs out there will not happily accept a larger diameter CCFL tube; in fact, many will work WORSE because they are designed to sit inside a reflector which collimates light from the sides & back of the tube to the front, and a larger diameter tube blocks that reflected light, if you can get it in at all without breaking it. Remember to use a caliper to measure diameter in mm; believe me, you'll guess wrong if you try to use a ruler.

I usually order tubes in pairs; they only cost around 10 bux each, and the shipping is the same for 1 or 2. If you are successful first try, you can save the other for a spare or experiment with Tesla coils... lots of fun.

Remember to work in the most dust-free location you can; if you can tolerate rubber gloves & mask, wear them for protection against the little bit of mercury vapor that can escape if a tube breaks.

mnem
CCFL? Weren't they a folk music group in the 60s?

 

Hi,

Thanks for the wise words! OK, a larger diameter tube is probably not the one to go for. I see exactly what you mean. My fault for being greedy with trying to get extra 'nits' for my buck.

I've measured up (with callipers):

The 12.1" screen looks like a 2.0mm x 250mm ccfl tube
The 13.3" screen looks like a 2.0mm x 275mm ccfl tube

... so I've ordered one of each (because they are cheap) and will report back.

This, incidentally, is way cheaper than a new screen, but you have to know what you're doing, and it can take a lot of time because it's fiddly and you have to keep everything very clean.

Cheers,
A

 

Hi,

Thanks for the wise words! OK, a larger diameter tube is probably not the one to go for. I see exactly what you mean. My fault for being greedy with trying to get extra 'nits' for my buck.

I've measured up (with callipers):

The 12.1" screen looks like a 2.0mm x 250mm ccfl tube
The 13.3" screen looks like a 2.0mm x 275mm ccfl tube

... so I've ordered one of each (because they are cheap) and will report back.

This, incidentally, is way cheaper than a new screen, but you have to know what you're doing, and it can take a lot of time because it's fiddly and you have to keep everything very clean.

Cheers,
A

 

I've tried this a few times with mixed results. I can see where it would be easy enough to do... But it is still VERY cramped in there and tough to get done on the Toughbook. When swapping your tube don't forget to take off the 3 little rubber spacers on the old CCFL. They are VERY small and clear so they can't be seen too easily. You'll feel them before you see them. Put them on the new tube prior to installation.

 

Ooooh TB - you are SO right! I knew there was something I forgot to mention. Those little clear spacers are there to maintain needed clearance for that collimating reflector to work; be very careful removing them (a little soapy water helps get them off in one piece); on older machines they can be well-stuck and a bit crumbly from age.

mnem
I'm looking for the LITE version...