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Dim LED on 33E - Printable Version

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Dim LED on 33E - Rhahm - 12-02-2001

The second LED digit on my 33E is dim compared to the rest.
I tried cleaning the back of the LED component with alcohol without success.

Is there a simple fix?

Thanks,

RH


Re: Dim LED on 33E - Tony Duell - 12-02-2001

If this machine used the older form of construction (ICs clamped to a flexible PCB, not soldered), then take it apart. Unclip the logic assembly from the top case
(be careful not to scatter keys everywhere!), then take the metal clips off the sides of the assembly and, with the keyboard face upermost, lift off the PCB/chassis plate assembly from the plastic IC holder. The display will probably fall off at this point.
Clean the pins of the display and all the pads on the flexible PCB with propan-2-ol (isopropyl alcohol). You can also carefully clean the pins on the processor chip (the 40 pin one). Reassamble the machine (the ICs all fit with the pin 1 end -- the notched end -- towards the display). Make sure the slide switch contacts are correctly fitted when clipping the logic assembly
back into the top case. Try it again. If that doesn't help,, then the fault is either the display itself, or or less likely the processor chip.


Re: Dim LED on 33E - David Smith - 12-02-2001

I have two spice series machines with the same type problem (one soldered, one compression). The problem seems to be in the CPU chip. The compression unit does the same thing with a different LED display. Contacts are all OK. I don't have another CPU chip to try though. I assume the soldered unit has the same fault. Let us know if you can get yours up and running again... I'd like to get mine working.