Fax machine teardown, what is missing ? How does it work ?

[lordvader88]

I took apart a 1990s FAX machine, some nice parts I can re-use/add to the collection. I'm having a hard time finding any schematics or repair threads on them, just google ads basically. Found 1 similar Panasonic manual tho.

At the front end of the machine there's about a 30cm/11" row of 29 SMD LED's, I thought they would be for lighting a page through, to read it. But I don't see anything 30cm/11" that would read it.

I don't see anything optical at all that size that could read what's on a page. Doesn't all fax machine have the ability to insert a page and copy/send it ?

I guess I only remember seeing fax machines in Die Hard 1/2

And how does the thermAL PRINTER WORK ? I found a 24cm/10" bar with what I guess is the heater element, it has a 15pin serial connector.

How does that work so that it can burn how ever many pixels wide 10" is ?

[james_s]

These machines use a linear CCD sensor, normally about an inch long. The bar of LEDs is usually green and illuminates a strip of the page, then a lens focuses the result into a line across the sensor consisting of a single row of pixels.

The printer is thermal, the bar you found is the print head, it's a row of single pixel wide heating elements that are activated in the proper sequence as the page passes over them. I've never looked at how they are controlled but I suspect they use a shift register.