Unsure about variety types of UV tubes for PCB exposure

[neko_whisker]

Hi I need your help. This will be my first time to build UV exposure box out of the scanner, for the purpose of making PCB. I am quite confused over the types of UV tubes, like UV-A, UV-B and UV-C. I have searched over the internet for answer but there are none or different answers. And I cannot find UV tubes here in this forum. For those experienced ones over, can you please advise me on the selection of UV? Also what do the correct type of UV tube look like when in off state?

 

[Hero999]

The subject has come up here before, although it probably isn't easy to search through everthing here.

You want UVA (blacklight) tubes, UVC is pretty dangerous and doesn't penetrate glass or transparancies very well and UVB isn't much better.

Insect killer tubes are probably the best to use, but you need the correct ballast and starter to drive it, which can normally be ordered from the same place as the tube.

If you don't want to worry about any specialist circuitry a blacklight compact fluroscent tube is pretty easy to connect up if you choose the type with a built-in ballast. Avoid blacklight incandescents as they are short lived and don't give you much UV light output, most of the light they produce is visible violet which will make some things glow but isn't much good for developing boards.

iUstrongly recommend reading RS's guide to fluroscent tubes

Other threads you might find useful.
https://www.electro-tech-online.com/threads/uv-light-in-scanner-project.26836/
https://www.electro-tech-online.com/threads/photo-etch-uv-tubes.24848/
https://www.electro-tech-online.com/threads/energy-to-a-light-blub-very-basic-question.25576/

Other sites you might find useful:
https://members.misty.com/don/f-lamp.html
https://home.howstuffworks.com/fluorescent-lamp.htm

 

[neko_whisker]

Hi Hero999,
thanks alot for your help