User “krzysztofh” presents another project of a pcb imagesetter. His previous one still performs well all the time but an exposure of a big board takes quite a lot of time- sometimes even half an hour. It turns out that one fluorescent lamp has to expose the board moving on the cart back and forth.
The new project assumes static exposure of a whole board with four 8 W lamps. The construction is obviously simple and the processor used is supposed to count set time down, control lamp connection and signalize an end of exposure with a sound signal and multiplex LED displays.
Atmega 8 was used but any processor can be used for the application because it does not have to do much. Time is displayed in seconds because, in practice, pcb exposure requires 70-90s This defined time is set to 60s, after turning on the power supply. It can be changed with up/down switches. The third switch serves to stop work with a 1s delay (to close the lid) and to stop it before the time (if necessary).
The imagesetter is supplied with a typical computer power cord. There is a mains switch mounted in the casing.
Boards are made on the basis of POSITIV 20.
There is a project diagram of the imagesetter, board patterns in Corel and in postscript form enclosed.
Link to original thread -
Naświetlarka do PCB