Repair LCDs Tandy EC-4025 (TI Collegiate) - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: Not HP Calculators (/forum-7.html) +--- Forum: Not remotely HP Calculators (/forum-9.html) +--- Thread: Repair LCDs Tandy EC-4025 (TI Collegiate) (/thread-9141.html) |
Repair LCDs Tandy EC-4025 (TI Collegiate) - John Cadick - 09-23-2017 01:16 AM I have a Tandy EC-4025. A couple of the LCDs have lost some segments. 1. Anyone know anything about the Calc? 2. Anyone have any tips on repairing/replacing LCDs? This calc is identical to the TI Collegiate. Pictures are available if anyone is interested. TIA - John RE: Repair LCDs Tandy EC-4025 (TI Collegiate) - jebem - 09-23-2017 06:07 AM (09-23-2017 01:16 AM)John Cadick Wrote: I have a Tandy EC-4025. A couple of the LCDs have lost some segments. I gave a couple of the Texas variants. They can be acquired for low cost here in Europe (10 to 15 Euros for a used in good working condition machine). Never tried to open them. But in these machine generations, usually the lcd uses a cheap unreliable flat cable built from plastic where composite conductive material is deposited to make the trace wires. This kind of conductive material will brake with aging. I have fixed other models by simply applying hot air over the flat cable. I just use a regular air drier as the tool. I have posted here before this technique applied on a Casio but can't find the message. RE: Repair LCDs Tandy EC-4025 (TI Collegiate) - John Cadick - 09-23-2017 07:08 AM Thank you very much, Jose. I'll try the dryer on it to see if that helps. I am hesitant to try to operate on it. 72 year old fingers don't work as reliably as they used to. 8^} John RE: Repair LCDs Tandy EC-4025 (TI Collegiate) - Steve Simpkin - 09-23-2017 11:56 PM That's a very interesting design. http://www.datamath.org/Sci/Modern/Collegiate.htm RE: Repair LCDs Tandy EC-4025 (TI Collegiate) - John Cadick - 09-24-2017 03:01 AM I really like the way it is designed. And it has complex number support. It looks like it may open fairly easily. Sounds like I may have a Sunday afternoon project tomorrow. Thanks, Steve. |