Please note that this store is currently in vacation mode. All orders received since November 28, 2022 will be shipped after December 07, 2022.
LCD replacement for TRS-80 PC-3 and Sharp PC-1250/-1251/-1255 pocket computers

LCD replacement for TRS-80 PC-3 / Sharp PC-125x

by The Half-Baked Maker


No tax for United States [change]
Stock available: 689

What is it?

This is a pin-for-pin compatible nearly exact replacement for the LCD module in the Radio Shack TRS-80 PC-3 or Sharp PC-1250/-1251/-1255 pocket computer released in 1983.

Why did you make it?

Many PC-3 and PC-125x pocket computers suffer from LCD degradation to the point where they are no longer useful. Apparently the seal around the LCD was of poor quality, and over the years moisture gets in and ruins the liquid crystal. The result is a display ranging from a few splotches to complete failure.

LCD showing degradation

I decided that it was important to bring all these dead PC-3 and PC-125x computers back to life by reverse-engineering the LCD and remanufacturing them.

What makes it special?

These LCDs were custom manufactured by Sharp for the PC-125x. Radio Shack had a rebranding agreement with Sharp, and named the computer the TRS-80 PC-3. Replacement LCDs were never available, and finding a working LCD is problematic, given the systematic failure of the seal.

I tried as much as possible to make the fonts and positions used for the indicators as identical to the original as possible.

Original LCD Replacement LCD

Instructions for replacement

I've made a video showing how to replace one of these LCDs. There are a few crucial things you have to be aware of:

  • Be sure to remove the plastic protective sheet on the top before installation.
  • After removing the bezel+LCD assembly from the original computer, you'll need to soak the assembly in acetone for 2 to 3 hours to get the old LCD unstuck from the bezel. Alternatively, I've heard about successes by putting the assembly on a hotplate set to 100C for about three minutes -- be very careful that you don't burn yourself!
  • Wipe the contacts on the new LCD and clean the elastomeric strips from your existing computer with isopropyl alcohol -- preferably the 99.9% purity kind.
  • Replacing the LCD will not guarantee a working computer! There could be other faults.
  • Getting the orientation right is crucial. The video shows how to do this easily.

Links to code and documentation

No additional links provided for this product.

Shipping policy

I ship via the United States Postal Service, every Monday (US Pacific time) except on USPS holidays, when I ship on the next open day. US destinations usually take a few days after that, UK/EU/JP about 2 weeks, and South and Central American destinations can take up to 6 weeks.

Product HS Code: 853120
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The seller

The Half-Baked Maker

Morgan Hill, California, United States
3 orders since Nov 14, 2022
I make all kinds of stuff. Sometimes the stuff can be useful to others. It's always Open Hardware, but I make some for sale if you want.