LCDeviations

The Trials and Tribulations of Getting a New LCD Display in a 30+ Year Old Pocket Computer

Having a hobby involving retro computing is something that usually fills one with nostalgia and joy. Even when a bit of repairing needs to be done, it's all worth it when you finally hold that now working vintage kit in your hands. If it can be repaired. If you can source the parts. 

Usually sourcing parts means buying knackered kits to use as donors. That works, but has the obvious drawback that you are reducing the amount of vintage pieces in circulation to get single pieces running again. Then you have failures that are endemic to the entire line, which means you won't be getting parts that don't have the same fault. 

Which brings us to early LCDs. The earliest LCD Pocket Computers all have a bit of a problem with their display modules. I'm talking about LCD bleed or rot. Over the years, water vapor seeps into the display module and causes black splotches, this ranges from an unsightly nuisance to making the display completely unreadable. 

LCD rot on one of my Sharp PC-1211s. 

Looking at Sharp this includes the EL-5100(S), PC-121x (aka TRS-80 PC-1), 1245 and the 125x(aka TRS-80 PC-3) series. I have yet to find a Pocket Computer from these model lines on eBay that don't have an LCD rot problem to some extent. Normally, that would doom these bits of computer history to the bin or, at best, a display piece.  

THANKFULLY, there are people like Robert Baruch and @poyokoma_danna over on Twitter who invest their time and money to get new replacement LCDs manufactured. They provide a huge service to the Pocket Computer community, making it possible to restore these beauties. The first time I even realized that you could get a new LCD for a Pocket Computer was because I stumbled across Robert's YouTube video👈 detailing the replacement process for a PC-1211 / Tandy PC-1. Also thankfully provided was a link to his Tindie store, which at the time sold LCDs for the PC-121x/Tandy PC-1 as well as the 125x/Tandy PC-3 series. Those LCDs are quite easy to replace if you follow his YouTube tutorial. 

5 repaired Pocket Computers, two ladies in waiting.

Through Twitter, I discovered that over in Japan, @poyokoma_danna had also tackled the same problem by having PC-1245 LCDs manufactured, so I ordered a few of those as well. He normally sells these locally only, so I had to sign up to a Japanese shopping & proxy service and have them shipped to me. This is not a cheap option! Without customs duties, were talking around €60 for a single LCD. I'm a collector and wanted a working unit badly enough to be willing to pay that price, but for most it's too expensive. Ordering from the States isn't exactly cheap either, but it's way more affordable than the Japanese option. (Edit 2026-01-27: this might no longer be true. Check your local tarif situation)

Luckily for me, on the other side of the Atlantic, Robert had not only ordered a test batch of 1245 LCDs, but also 1246/1247 modules as well. He graciously offered some for me to test, and provided much needed support during the installation process. I can't thank him enough, he's an awesome person, and a pretty impressive dragon as well. (And I still feel guilty for having taken so long to write this blog post.) The process of replacing the LCD on a 1245 is finicky, but can be done. 

Removing the old LCD from the 1245 is the exact same process as in Robert's video, disassemble the Pocket Computer, carefully* bend the prongs up that hold the bezel in place. Remove the bezel with the glued in LCD and take out the elastomer strip for safe keeping. DO NOT LOSE IT! Seriously, those aren't easily replaceable, but I'm working on it. Dump the bezel with the LCD in a ziplock bag of acetone and let it soak for a few hours. I usually just leave it soaking over night.

LCD soaking in acetone to separate the metal bezel and the LCD.

 

Now begins the part that took me the longest. Position the LCD so that it lines up exactly with the contacts on the board. This was a simple affair with a 1211 or 1251 because that coincides with the LCD module being pressed up to the left side of the bezel. All you need to do is make sure that the LCD stays in place while inserting it. That's where a paper shim comes in handy. With the 1245, it becomes a bit more difficult. Pressing the LCD smack up to the bevel edge on the left side doesn't guarantee that the contacts on board and LCD will be lined up correctly. A misaligned LCD looks something like this:

Oops, let's do that again.

 

Once you do get everything aligned, preferably by following the expansive documentation you found on Robert's page on the PC-1245 LCD replacement. It should look like this:



 

There, much better!

That wraps up this short description of the LCD replacement process. I hope it helps and maybe inspires you to try replacing your own defective LCDs.

*Footnote: I can't stress this enough. The metal prongs are easily broken off by using too much physical force and you also risk sliding off and scratching up traces or other important pieces. I use a very thin flat head screwdriver to lift the prong up just enough that I can use a fine wooden brush handle to do the actual bending.

Oops. Should have used a softer tool, and less force.