H/PC Newbie Posts: | 3 |
Location: | United States | Status: | |
| Hi All,
I've had my Jornada 728 for a few weeks, and I'm pleased with it, aside from the nagging problem of it being too darn dim to read while outdoors. The J520 I "upgraded" from finally died, but it's screen was very bright and could be read in all but direct sunlight.
The CCFL in the Jornada 6xx and 7xx is a single tube, 2.6mm in diameter and 158mm long. Operating voltage is 380v, and operating current is 5mA (just under 2 watts).
A replacement CCFL from backlight4you.com costs about $40 or so.
Being a DIY individual, plus being cheap, I brought my google-fu skills to bear on the problem, and soon located the BF3160-20B.
It's a CCFL, 3mm in diameter, 160mm long. Operating voltage is 345V and operating current is 5mA. Cost is $11 + shipping from Mouser electronics.
As CCFL's age, they get more pink, take longer to start up, and get progressively dimmer. The CCFL in the jornada is probably the original, and as such, nearly a decade old.
Once I have the CCFL tube in my hands I'll drag out the digital camera and take pictures as I work on fitting the new CCFL.
I'll be sure to take before and after photos at identical exposure conditions to try and show the brightness of the screen accurately.
Hopefully I'll end up with a easy transplant and a brighter screen for far less money than the $40 replacement bulb. At worst, I'll either put the old bulb back in or break down and order the expensive bulb.
The replacement bulb should arrive early next week (9/14-9/15), and I should get to changing it out later that week.
As an aside, I have a defunct laptop screen here in front of me. Depending on what I find in the Jornada, I may try scavenging the bulb reflector and trimming it to fit, and/or scavenging the diffuser panels from the laptop screen and cutting them to fit. We'll see.
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H/PC Newbie Posts: | 3 |
Location: | United States | Status: | |
| Hi All,
Well, I finished up the work and ran my Jornada at maximum brightness, "Outdoors", on the AC adapter for awhile. No problems at all.
The answer to the long awaited question - Is it Brighter?
Yes. Most assuredly. The pictures didn't do so well at capturing the difference, even at the same exposure settings and conditions. But with the new CCFL lamp, I get the same brightness on "Dim" as I used to on "Outdoors." It still isn't quite bright enough to read outdoors, unless you're in the shade and carefully keep any glare off the screen. So I didn't get the brightness I wanted, but at least I got a brighter screen.
On a scale of 1 to 10, with 1 being easy and 10 being impossible, I give this upgrade/mod about a 5. The process is pretty straightforward, but the parts involved are very delicate, and small. There's some cutting and trimming necessary to get the CCFL to fit into it's bezel, and good precision soldering skills are necessary to make the tiny solder joints to join the CCFL leads to the supply wires.
I don't recommend this for the general user to do. I'm experienced in laptop and small, fiddly repairs such as this. The case of the Jornada uses clasps to fasten it closed, and they're easily broken by manhandling them. A plastic spud tool is one of the very few ways to open the case without leaving marks all over it.
Here's how I went about the work, but let me state:
*I* am *NOT* responsible for *YOUR* work. CCFL lamps contain Mercury. Solder contains Lead. Soldering irons get hot. Objects in mirror are closer than they appear. Contents may have settled during shipping. Percentages based on a 2,000 calorie per day diet.
I am *NOT* responsible if you try this and end up bricking your Jornada. It worked for me. I don't deliberately give bad advice, but I am only human, and I make mistakes sometimes. My way may not be the Best way, so if you're in doubt, get a second opinion.
With that out of the way,
I used the Mouser part number 560-BF3160-20B CCFL. It's electrically identical to the original lamp in the Jornada, but it's 3.2mm in diameter (vs 2.6), and 160mm long (vs 158mm). It *DOES* fit, but requires some modification to the bezel.
First, backup all your data onto compact flash. Remove the CF card, PCMCIA card, backup and main batteries.
From here on out, *FRONT* is the side of the screen you see and use the stylus on. *BACK* is the opposite side. *BOTTOM* is the bottom, where the CCFL lamp lives.
Open the screen to 90 degrees. Once you start disassembling things, *DO NOT* try to open or close the screen. You'll most likely end up breaking the screen bezel, and it'll be an ugly repair.
Remove the two Hp badges on the lower front of the screen clamshell. Remove the two Torx screws.
Using your spud tool or similar (NOT a screwdriver or exacto blade), gently work the clasps open. The back of the screen bezel snaps *over* the front, so pry the *back* part's edges outwards and backwards gently. If it doesn't want to go, leave it and go work on the other side of the screen bezel.
Once you get the screen bezel off, you'll see the back of the LCD screen assembly, and the orange/brown screen cable. This terminates in a small flat-cable connector and the inverter. *GENTLY* lift the dark brown retainer on the flat cable connector on the LCD screen assembly. The cable should remove easily. Unplug the CCFL from the inverter (not the inverter from the orange/brown screen cable). Gently press on the front of the LCD screen assembly and it should pop right out of the screen bezel. Set the rest of the Jornada aside.
Now you have the LCD screen assembly. It consists of the LCD screen and it's frame, and a smaller black bezel set into it that contains the CCFL and it's diffuser assembly.
Along the top and bottom on the back of the LCD screen assembly you'll see small bent fingers that keep the diffuser assembly in place. Gently bend these fingers straight and remove the diffuser assembly. There may be some transparent yellow tape holding things together. Gently cut it with a razor blade or exacto. Once you have the diffuser assembly out of the LCD assembly, set the LCD assembly aside.
Remove the back cover of the diffuser assembly. It's a metal plate that probably has "Hitachi" and some other info printed on it. Now you'll see a white sheet, with the CCFL at the bottom of it. The CCFL is held in place by a "loop" of reflective plastic. Carefully pull the white wire of the CCFL out of it's groove. Then carefully press on the front of the assembly, and the whole diffuser panel should come out of the black plastic bezel. There are 3 sheets on the front of the diffuser. Two are reflective on one side, the third is most likely secured to the diffuser on the top, and the plastic reflective "loop" that secures the CCFL on the bottom. *MAKE A NOTE* on how the reflective layers are oriented. Be careful, as any of the diffuser parts scratch easily.
Gently peel the third diffuser sheet off the front of the diffuser, and you should be able to remove the CCFL. *BE CAREFUL!* It's extremely fragile glass!
Start the soldering iron heating up. You want to use a high quality, fine gauge electrical solder. Not plumbing solder. Use a soldering iron with a fine tip, a 20-25W iron will do nicely.
I secured the bulb in a small alligator clip padded with a scrap of paper towel folded about 4x. Gently slide the silicon covers at the ends of the lamp up the leads to get them out of the way.
Melt the solder joint and gently pull the lead free from the CCFL's terminal. Repeat for the other side.
Grasp the new lamp in the same way.
Solder the lead to the CCFL's lead *AS CLOSE TO THE TUBE AS YOU CAN!* You don't have to directly apply the iron to do so. The CCFL leads are copper, so you can hold the iron on the CCFL lead a few mm away, touch some solder to it to make good thermal contact, and hold the wire lead to the CCFL's lead as close to the glass as possible. In a second or two the leads should solder themselves together. Remove the iron, keep the hand holding the wire lead steady, and give the joint a few seconds to cool. Don't tug on the lead!!!! Repeat for the other side. Once that's done, and the tube cools off for a couple of minutes, trim the excess off the CCFL leads. I use nail clippers. Slide the silicon covers back into place on the ends of the bulb. Be careful not to split them, as this tube is larger than the old one.
Armed with your freshly leaded CCFL, set it in place in the black bezel, and you'll see what has to be trimmed. I trimmed of the thin plastic "end" of the channel it sits in, and whittled down on the other end to make room for it. Once you have a good fit, gently put the CCFL back into the plastic "loop" on the bottom of the diffuser, leads pointing downwards, and re-assemble the diffuser and put it back into the LCD assembly.
At this point, set the LCD assembly carefully in the Jornada's screen bezel, and hook up the flat cable. Plug in the CCFL, and secure everything lightly with scotch tape.
KEEP AWAY FROM THE INVERTER!!!! It won't shock the crap out of you, but it'll give you one nasty stinging burn from hell. Like a red-hot needle boring into your finger. Nasty.
Put the main battery back in (don't worry about the backup battery for now), and power the unit up. With any luck, you'll have a bit brighter screen! If the screen looks dim and somewhat reflective, you got one or both of the reflective sheets in the diffuser assembly in backwards.
Once you get the screen looking as it should, go head and button everything up. Be careful and gently getting the screen bezel snapped back together. Don't forget the Torx screws.
Reinstall the backup battery, then install your main battery and flash card. Restore from your backup, and enjoy!
Problems :
Screen is still very dim - You probably got one of the diffuser sheets in backwards, *OR* you didn't get the assembly properly aligned when reassembling. With the larger CCFL, it's a little bit of a squeeze to get everything back together.
If all the sheets are in correctly, and it's *still* dim, your inverter may be weak and / or going bad. Repairing the inverter is beyond the scope of this article. Probably best to buy another Jornada.
If the screen lights intermittently, you probably have a bad solder joint to the CCFL leads. Pull it back apart and re-flow the joints.
Well, that's about it. I can't think of anything I left out. Disassmbly and reassmbly are pretty straightforward. Once again, I don't recommend this for the faint at heart. The CCFL I used isn't an exact replacement, so some modification of the bezel where the lamp fits into is needed. I'd contemplated trying out some diffuser material I scrounged from a defunct laptop, but that would have required substantial modification to the diffuser assembly. Battery life shouldn't be affected, as the replacement lamp draws the same power as the old one, and should provide a bit more light.
The new CCFL has a *very* slight color tint to it. It's either green or blue. I'm color blind to light green and light blue, so I can't tell the exact color. The old CCFL had a slight warm pinkish hue, typical of a CCFL a good way through it's life. The new CCFL reaches full brightness almost instantly, whereas the old one took a second or so to reach full brightness. The slight color tint in no way affects the usability of the device.
Pictures trying to capture the difference in brightness didn't turn out so well. I've some pictures of the process, if anybody is interested.
If anybody wants to try this themselves, let me know!
Hope it helps!
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