Seiko M4024 Problem, Please help!


New member
Greetings to all.

I recently built a LCD enclosure out of a Radio Shack Project Box, using a home-made Voltage Regulator (7805A) circuit, and a Seiko M4024 EL Backlit Display.

I have since removed the EL backlight (un-soldered) and ditched the inverter due to some problems I had with the unit. And I don't need the backlight anyways.

I have physically tested ALL the LCD wires and pins, everything checks out. The LCD even worked great for a while!

Recently, actually, as soon as I hooked the LCD up to my P/S (using the 12v line- the regulator jacks this down to 5v), the upper half of the display will not function. Sometimes it stays blank, sometimes it goes black with a really bizzaro "PI" (the math symbol) flashing here and there incredably fast when the upper half turns black. The bottom half works, save for a few bizzare charactors that flash from time to time. This all started when I hooked the LCD up to my main P/S in my computer. Before I just had a Power Source sitting on my desk that it was hooked up to for testing.

I'm using LCD Smartie 5.1 with Port95NT installed. As I said before, the display was working just great.. Not anymore.

Any suggestions why the upper half of the LCD display isn't working? I head that these Seiko units (mine is a 4x40) have TWO controllers (both that HD77 or whatever the chip was- the most basic and compatible chip out there), that control 80 charactors each (two lines). Is it possible that one chip may be zapped?

I'd really like some help if you can offer any. I spent alot of time preparing this LCD unit to make it look and work nicely, and now this happens..... :-(.

Keven Tipping
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New member
You have been using an M4024 I am quite keen to buy some do you know any where I might find stocks?