Replacing dead screen on my HP17BII with one from HP27S?


My 18 month old son just threw my 17BII on the floor when it was turned on. The screen has stopped working and it is black over part of it, so I assume is is a goner. I have two HP27S's that are in hardly used condition but because they don't have RPN I don't like using them? Is it feasible to put a good screen from a HP27S in my HP17BII? I am not very good with electronics so would have to get someone to do it for me. If it's feasible can anyone recommend someone here in Australia who could do it for a reasonable price? Does anyone have any idea what this might cost? Otherwise I can buy a new HP17BII+ or a used 17BII ex ebay. The just dead 17BII is a used one that I bought on ebay to replace one that got drowned in a glass of wine. I bought this because I read some forum comments that the older model is superior to the new one. Has anyone got any thoughts on this + whether I should just get another machine rather than muck about swapping screens over?





I wouldn't bother fiddling with replacing LCDs, effectively wrecking even more HP calcs;-)

My suggestion: Sell the 27S units, and buy another used 17BII, either from TAS or elsewhere.




Hi Raymond

Thanks for the advice. I just remembered I have the older 17BII that had wine split on the key board. Thanks to advice I got on this forum I was able to revive it several times but it eventually died. The screen on this one is OK, so assuming that on my recent accident the screen is the only issue, I could feasibly make one good one out of two dead ones. This would avoid me having to wreck one of the good 27S's. I have no idea how difficult it is to swap the screens so if I'm totally on the wrong track let me know. Looking at ebay I can probably pick up a good used 17BII for $50.




Indeed, please do not sacrifice a 27s for a 17bii. That is moving in the wrong direction.



Some people (PICK ME! PICK ME!) would gladly give you a mint (or two mint... PICK ME!) HP17BII+ for one of your HP27S...

About swapping LCD´s: I have once tried, and let me tell you that the 'operation' involves many steps: disassembled a calculator with many plastic rivets, totally remove the mainboard by twisting six metal tabs that may crack and you´ll be in trouble setting the mainboard back in place, choose between removing the 'metal chassis plate' with the keyboard contacts OR the LCD that is glued in the chassis plate, then bringing it all together in one piece, all of the steps above backwards...


Luiz (Brazil)

P.S. - just in case... PICK ME!

Edited: 10 July 2010, 3:32 p.m.


Hi John!

I've got a dismantled HP17BII (it have a "keyboard-not-responding" malfunction). If you want to trade your one 27S to my 17BII please send me a private email!

Thank you!




I had no idea that HP27's were so attractive. To me the fact they don't have RPN makes them painful to use. Are they a lot rarer or the fact they are a scientific calculator that makes them appealing? I'll keep you in mind Luiz if my repair process fails. I've already started trying to make one good 17BII out of my two bad 17BII's, so both HP27's live on. Basically I have nothing to lose apart from wasting my time.

I'm following the procedures I found in this link headed "HP Pioneer Observational Internals"

I've now got the two halves of the first calculator separated after using a small drill bit to ream out the plastic heat stakes inside the battery compartment.

I've now hit a snag with removing the board from the front half of the case.I've twisted the 6 tags so they line up with the slots in the PCB but the board won't easily pull away and feels like it's jammed. It feels like it's another problem, different to one or more of the tags not being lined up exactly with a slot. Any suggestions on what to do next? I'm worried that if I try and use a small thin bladed screwdriver to lever the board out near the tags I'm going to crack the board. Any suggestions would be most welcome.

The link explains how to remove and replace the screen from the steel frame. Hopefully this will go smoothly but any extra comments or ideas would be appreciated.




Indeed, please do not sacrifice a 27s for a 17bii. That is moving in the wrong direction.

I sacrificed a good 17B for a 27s. right direction?

HP-27S LCD transplantation


Hi, John;

FYI, here in Brazil we have an 'e-bay' local equivalent called 'Mercado Livre' (could translate to Free Market). There are two HP27S´s being sold right now. One is new in the box for about R$450,00 (~US$255,00) and the other is just the calculator and protective cover, for about R$290,00 (~US$165,00). Used HP17BII can be found for less than half of it...

I like the HP27S because it is versatile. It lacks programming (but it has the SOLVER) and RPN, but it offers a lot more. If you are a Production Engineer the HP27S is a handy 'swiss knife' calculator. Of course, you can buy a new HP50G and customize it to go far beyond the HP27S, but the HP27S is from 1988, an almost 23 Y.O. design. And was available NIB from HP for no more than four years. It is a rare piece.

One of the guys that has been restoring and repairing calculators is Geoff Quickfall, along with some others. His works in restoration and repair led him to write a book about it. I consider it a must have...

Now for the HP17BII repair. I once rebuilt an HP42S from a non-working HP17BII 'who' donated the LCD and the keyboard contacts (the whole metal plate) and another HP42S with a relatively good case and mainboard. I also used this little 'frankencalc' as my first 32KRAM transplantation, and the little thing survived! Well, it has two columns and one row in the LCD that do not turn on (its 'scars'), but hey! That´s fine, I use it regularly.

I know that 'peeling' the keyboard faceplate out allows the plastic rivets to be accessed and the frame to be replaced, but I did that only with an HP15C I rebuilt from an HP11C´s case and mainboard. I removed the 11C´s IC´s and kbd faceplate and 'inplanted' the IC's and faceplate from two different HP15C's. I must tell you I had a lot of difficulties do remove the kbd faceplate, but one of our regular contributors has the skills and have found a way This the 'frankensister' or 'frankenbrother' of teh other one... (sound too familiar, I know). The cosmetics are not exactly what I expected, but this little one is also working for many years.

About the mainboard: there must be a better way to remove it, if it feels jammed than I'd think twice prior to try to pop it out with a cutting blade. If I may, I'd suggest using something that bends itself instead of something that might bend the calculator case, the PCB or that might damage something...

Not so much of a help, though, but that´s what I'd try to.


Luiz (Brazil)

(P.S. - I'd LOVE to have an HP27S like the one announced in 'Mercado Livre' here, and I have an HP17BII of the early type - brown case, no language option - but I am not so sure if it is worth risking the mail for a trade... Picking me for a trade was more like a wish than a request... Others, fairly closer to you, would benefit in such trade, and I'd encourage so)

Edited: 10 July 2010, 10:00 p.m.


I had no idea that HP27's were so attractive. To me the fact they don't have RPN makes them painful to use. Are they a lot rarer or the fact they are a scientific calculator that makes them appealing?

Bear in mind that the 27s was born in the era when HP finally realized there was a huge potential market they were missing: folks (Like me!) who find RPN a pain to use, but who longed for the legendary HP quality. So they came out with, 10b, 14b, 17b, 20s, 21s, 22s, 27s, all "algebraic" models, and later 17bii, dual mode, as you know. IMO the 27s is by far the best of them, combining both scientific and business functions. And it's Solver is just fabulous. The 27s is so good that even some RPN users (gasp!) get it and "put up" with its algebraic-ness.

The 27s is so good that even some RPN users (gasp!) get it and "put up" with its algebraic-ness.

That would be me. except that I "embrace" rather than "put up with" the algebraic.

I kick myself for not looking into this machine long ago. In 1995, when I lost my 11c, I remember seeing this 27S in the store. I turned my nose up at the "Algebraic" thinking, "I want something that is as like my 11c as possible." So I got the 32sii. Looking back, I chuckle. The 27s is fantastic and soooo much better than the 32sii for my needs.

Maybe I shouldn't post this. It will drive up the prices on ebay.

Possibly Related Threads…
Thread Author Replies Views Last Post
  Prime screen scratches - Use a screen protector Eelco Rouw 11 3,336 11-19-2013, 10:16 PM
Last Post: Eddie W. Shore
  Stylus for Prime screen steindid 6 2,366 10-22-2013, 02:06 AM
Last Post: Alberto Candel
  Sending from graph to home or CAS screen Richard Berler 6 2,283 10-06-2013, 03:29 PM
Last Post: Tim Wessman
  HP48GX screen replacement Francisco Quiles 9 3,892 10-03-2013, 09:17 PM
Last Post: Francisco Quiles
  hp50g screen weird line Sok-khieng Chum Hun 2 1,617 09-10-2013, 08:11 AM
Last Post: Sok-khieng Chum Hun
  New screen on pictures of new Sharp EL-9950 Mic 4 2,082 06-10-2013, 10:40 AM
Last Post: Mic
  HP Prime should have higher resolution screen LHH 5 2,116 04-25-2013, 10:00 AM
Last Post: bhtooefr
  Previously dead WP 34S is resurrected! JayV 2 1,304 04-18-2013, 12:41 AM
Last Post: Walter B
  Creeping black pattern on HP-11C screen Larry Gagnon 6 2,103 04-12-2013, 10:09 AM
Last Post: Peter Murphy (Livermore)
  HP-42S with Electroluminescent screen and simple I/O port Jose Poyan 8 2,743 03-27-2013, 07:11 PM
Last Post: Jose Poyan

Forum Jump: