HP Forum Archive 14

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LCD replacement on 11C,12C,15C,16C Message #1 Posted by Chris Woodhouse on 30 May 2004, 2:53 p.m. Correct me if I am wrong, but I believe the way you replace or clean the LCD from 11C, 12C, 15C or 16C is to open the back and remove the all or most of the little plastic rivets that hold the keyboard down, then you can pull the LCD screen out. The main disadvantage being it is hard to get the little plastic rivets back in place to hold the keyboard tight. I read that one person started an attempt to pull up the brushed aluminum sheet that surrounds the display but they stopped because it was going to destroy the face plate. My question is, once you get the face plate off can you then get the LCD out? The reason I ask is because even though the face plate would be destroyed in the process, it is a pretty simple bent aluminum sheet that could easily be remade with the right tools. Chris W Bring Back the HP 15C

Re: LCD replacement on 11C,12C,15C,16C Message #2 Posted by Randy on 30 May 2004, 4:20 p.m., in response to message #1 by Chris Woodhouse If it is an early Voyager, cleaning or replacement is straight forward as the logic board is seperate from the keyboard, you simply lift it out from the back. If it is the more common single board model, removing the front aluminum bezel will get you access to the LCD for cleaning but leave you with a bent bezel. It is **very** difficult to remove without some distortion. Better to use canned air from the back and blow it out. Stubborn specs can sometimes be dislodged with a small strip of coated paper. Don't use anything metallic or really stiff as it is very easy to scratch the lens or the even softer polarizer on the LCD. If you goal is to replace the LCD, the entire pc board must be removed for access, and yes, all 40 heat stakes must be cut away to get it out.

Re: LCD replacement on 11C,12C,15C,16C (earlier models) Message #3 Posted by Vieira, Luiz C. (Brazil) on 30 May 2004, 6:55 p.m., in response to message #1 by Chris Woodhouse Hi; although I had myself a bad experience with this earlier "construction" type, the first Voyagers had a separate assembly with all "active electronics", meaning all IC's, the LCD and three passive components (two capacitors and one resistor) built in one flex circuit board and "housed" with the LCD metal frame and a plastic structure. This assy is easily removed and there is no need to cut any of the plastic rivets out. I consider handling this LCD assy very time consuming and you'll surely need some special tools to avoid destroying (wrapping or even tearing apart) the flex circuit. Now, based on my own experience too, I removed at least three of these aluminum face plates, but even when you take care, as Randy stated (and I second him completely), it is too d... hard not bending it or causing irreversible distortion. About building replacement parts: that would be an idea and I must confess I liked it a lot. What I don't understand is why HP cannot sale this frame separately? It's still being produced somewhere (HP12C) and it's not too expensive, I think. Well, I'd rather see one of my Voyagers with a golden faceplate instead of a damaged one. The HP12C Platinum frame is different and is designed to hold the new HP Invent logo, but I'd not care using this one, too. Is there anyone here that can contact HP and request information about the source of these faceplates? Please, let us know. Cheers. Luiz (Brazil)

Re: LCD replacement on 11C,12C,15C,16C (earlier models) Message #4 Posted by Chris Woodhouse on 30 May 2004, 9:15 p.m., in response to message #3 by Vieira, Luiz C. (Brazil) Quote: What I don't understand is why HP cannot sale this frame separately? It's still being produced somewhere (HP12C) and it's not too expensive Well it is not hard to make, the only thing I don't know for sure is where to buy aluminum sheet that already has the brushed finish but I'm sure it wouldn't take too long to find that. Then I could have my brother machine the hole for the LCD on his mill and then anybody with a small sheet metal break can bend it. Now if you want to just get one for the 12C, we just need to find out where the factory that makes them is, get to know someone who works there and buy about 500 of them. They Probably only cost $0.50 each and we could sell them on ebay for $10 each :) Someone reading this forum is bound to know where the factory is or can find out and then someone else is bound to live near the factory and can find someone that works there. . . . Chris W Bring Back the HP 15C

Protective glass (shield) Message #5 Posted by Vieira, Luiz C. (Brazil) on 31 May 2004, 12:28 a.m., in response to message #4 by Chris Woodhouse Hello, Chris; Still keeping track with your original and very welcome idea, I'd also add that there is a coated "glass shield" (not a glass-made shield, instead some sort of polymer) that is "glued" to the aluminum frame. If we find the original manufacturer, I guess that this protection will be already built in all sold units. If the replacement is produced by the process you pointed out, than the "discarded" frame must donate the original glass. Have you ever seen one of these frames removed? Did you notice the protection? The original protection is coated with some transparent material that enhances transparency. Someone once mentioned what is this coat made of. (if you scratch the protective "glass" you'll notice that the coat cracks) Best regards. Luiz (Brazil) Edited: 31 May 2004, 7:13 a.m.

Re: LCD replacement on 11C,12C,15C,16C Message #6 Posted by JDH on 30 May 2004, 10:33 p.m., in response to message #1 by Chris Woodhouse On a related topic, I had an HP 15c that had a number of bad scatches on the silver plate. I ended up using a fine grade sandpaper to get it back to the bare aluminium. If done carefully and polished evenly (same direction) it looks as good if not better than a new one. This is a good fix for badly scratched calculators.

Re: LCD replacement on 11C,12C,15C,16C Message #7 Posted by Alex on 31 May 2004, 12:31 a.m., in response to message #1 by Chris Woodhouse Let’s assume that you have a HP-15C that is not available anymore in stores and is going for about $300 to $400 at eBay. Let’s assume again that you want to fix/repair or even just clean the LCD lens only. Buy a new HP-12C for about $70 at Office Depot. Remove the entire LCD/chip module on both calculators and replace your 15C LCD with the LCS from the 12C. It works. I did it. Instead of messing around trying to clean it and in the process you risk of damaging the entire machine. True, it will cost you about $70 but now you have a brand new LCD on your supper 15C machine. Also you can replace the aluminum silver plate if your has scratches. You can also switch the name plate from your 15C to the new silver plate if you want to be perfect. Alex

Re: LCD replacement on 11C,12C,15C,16C Message #8 Posted by Vieira, Luiz C. (Brazil) on 31 May 2004, 12:47 a.m., in response to message #7 by Alex Hi, Alex; I knwo that the newer HP12C have a different type of LCD. Did you manage to put the newer LCD working with the earlier HP15C hardware? The contacts' alignment do not match, and there was a discussion here about different working voltage: newer HP12C use a 3-volt cell, while the earlier Voyagers (HP10C, 11C, 15C, 16C and some HP12C) work with 4.5Volt (3×LR44 cells). I'm very interested to know what did you do. That would solve a lot of problems for many of us. Cheers. Luiz (Brazil)

Re: LCD replacement on 11C,12C,15C,16C Message #9 Posted by Alex on 31 May 2004, 1:22 a.m., in response to message #8 by Vieira, Luiz C. (Brazil) Hi Luiz, I did exchange my LCD a couple years ago. I simply got a new 12C from the store and did the replacement myself together with the silver and the name plate. I did not got any problems while aligning the contacts. But, if you do see that the alignment is off then you can make then match if you are into the electro hobby stuff. Now, on the new 12C that you can get it in stores today for about $70 it may be that the contacts and the voltage doesn’t match but still you can go around this problem. Get an older 12C from eBay for about $25 ( that’s the average price for a 12C) and you will have many spare parts to do the rebuilding on your supper 15C machine. The older 12C is running on 4.5 volts and the construction of the LCD is identical. Alex

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