Some articles

[jknightandkarr]

I was looking over the articals area, particuarly this one http://www.electronics-lab.com/articles/etching/index_en.htm and noticed that some areas of the auto translated from greek to english areas are not understandable such as this part...

Turn on the UV box lamps because need roughly 5 thinly in order to they reach in their biggest brightness. Thus you do not use UV box front pass 5 thinly since they turn on lamps. Be not extinguished lamps afterwards the appearance pcb if you are to present above, because lamps steams of mercury it should freeze in order to they turn on again. Extinguish since you have finished all the process of report.  ???

I have no idea what in the H E Double Hocky Stick that even means, nor could I make heads or tails out of it.  May want to concider rewriting them so people can under stand them.  Cause it confused the crap outta me.  :-\ ???

Joe

 

[Hero999]

I haven't seen the original article.

Here's my guess at the meaning, going from the poorly worded paragraph you've quoted.

The project uses high pressure mercury vapour lamps which take five minutes to warm up and produce full light output.. This is because the light producing discharge requires mercury in the gaseous state and when the lamps are cold, the mercury is still a liquid. Unfortunately the lamps can be damaged if started when the mercury is in a gaseous state and the lamp pressure is still high so they need to be left to cool for five minutes before they are restarted.

Most modern high pressure mercury lamps don't produce much UV because they are encased in a phosphor coated shield which converts most of the radiation to useful visible light. The shield can be removed but this might be a bad idea as some lamps have a safety device which stops them from working with the shield removed. Even with the shield removed, most of the UV radiation from a high pressure mercury lamp is in the UV region which isn't optimal for exposing photosensitive bulbs.

You can buy special black light high pressure UVA lamps designed for blacklight cannons (also called beehive lamps) which are used for theatrical effects and can be purchased from, stage, DJ and audio supply shops.

Here's an example of such a lamp: http://www.planetdj.com/i--LL-400BLB

Note that you'll need a suitably rated ballast and igniter to use the lamp, although you can buy lower powered lamps with it built-in.

 

[jknightandkarr]

What about a floresent tube black light?  I have a black lite from Lights of America with this info on the bulb F17T8/BLB (RB17T8BLB)
Color Temp=30,000K 
CRI=47, 8,000 hrs (358)

Joe

 

[Hero999]

What about a floresent tube black light?  I have a black lite from Lights of America with this info on the bulb F17T8/BLB (RB17T8BLB)

Yes, fluorescent blacklights will work but are nowhere near as powerful as high pressure mercury vapour lamps. To be honest, I think high pressure mercury vapour lamps are overkill, fluoroscent blacklights should be more than powerful enough.

Color Temp=30,000K 
CRI=47, 8,000 hrs (358)

That doesn't make any sense, a colour temperature and colour rendering  index can't be applied to a blacklight.

 

[jknightandkarr]

Cool, thanks now I just have to get another fixture for my black lite, stupid fixture blew last nite before the original bulb did....... :  >

As for the index & temp, no idea, that's just what was printed on the bulb.  Anyhow, thanks for the help.  ;D

Joe

 

[Hero999]

It might be that you used the wrong tube for the ballast.

What colour what colour is the tube when off and when lit?

A black light will be white when unlit and bright blue when lit, a black light blue with be very dark blue, almost black when unlit and deep violet/blue when lit: either a black light or black light blue will do.

The article uses high pressure mercury vapour lamps which are totally different to fluorescent lamps which are low pressure mercury vapour lamps.

Regardless of what type of lamp you use, the ballast needs to be matched to the tube otheriwise either the ballast or tube could be damaged.

 

[jknightandkarr]

Actually its the tube that came with it the fixture.  The tube is almost black when unlit.

Joe

 

[Hero999]

It's probably just a bad ballast, just make sure you order exactly the same type.

As the tube is black when unlit, it's a black light blue tube which is perfect for etching PCBs.

For a decription of colour temperature and rendering index, see the following links:
http://en.wikipedia.org/wiki/Colour_temperature
http://en.wikipedia.org/wiki/Colour_rendering_index

 

[jknightandkarr]

Checked the price on em today at work & Wally World only want's $10 for em, so at least it's cheap.  Thanks for the help. 

Joe