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Messages 20265 - 20296 of 23865   Oldest  |  < Older  |  Newer >  |  Newest
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20265
... Complete with a free trojan that turns your PC into a spam or DDOS zombie. If people want free EDA software, gEDA and PCB is fully functional and it's...
Dylan Smith
alioth10
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Mar 1, 2008
10:00 am
20266
I did a little more testing of UV LEDs this weekend. The LEDs are plugged into a solderless breadboard and driven with a variable external power supply I tried...
javaguy11111
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Mar 3, 2008
2:12 pm
20267
... From: "javaguy11111" <javaguy11111@...> To: <Homebrew_PCBs@yahoogroups.com> Sent: Monday, March 03, 2008 2:12 PM Subject: [Homebrew_PCBs] Re: UV LED...
Leon
leon_heller
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Mar 3, 2008
3:06 pm
20268
The half angle is 10 degrees which is the half power point according to the data sheet from Best Hong Kong. So if I want the two LEDs half power point to fall...
javaguy11111
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Mar 3, 2008
6:57 pm
20269
While at the local Wal-mart I picked up a Scotch (3M) TL901 9" laminator for $US25.00. After taking it apart and verifying its usability for toner transfer, I...
josemj1
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Mar 3, 2008
7:10 pm
20270
I also got the 390-395nm BestHongKong LEDs. To test the exposure time I made a 3x3 square array as you did, but with 15mm pitch, not 13mm. To look for...
Adam Seychell
a_seychell
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Mar 4, 2008
8:52 pm
20271
... What if you built your exposure box with mirrors on the sides? It would appear to the pcb like an infinite grid of LEDs....
DJ Delorie
djdelorie
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Mar 4, 2008
9:29 pm
20272
I am using the 395-400nm LEDs. Since there is a strong UV component to the LEDs I am not sure if a visual test for uniformity is going to be accurate. Since I...
javaguy11111
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Mar 4, 2008
9:43 pm
20273
... of the ... away. ... I think all the mirrors would do is reflect the light that is at a high angle of incidence and cause broader lines. Light at lower...
javaguy11111
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Mar 4, 2008
10:17 pm
20274
Damon, If you do the maths, you'll find that intensity for an infinite array of infinitesimal small point sources gives constant light intensity at all ...
Adam Seychell
a_seychell
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Mar 5, 2008
4:14 am
20275
The distance from the board is easily adjusted. If it needs 2 inches fine. If it needs 1.42, that is fine to. Thanks for the pointer to the pdf. I will take a...
javaguy11111
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Mar 5, 2008
5:48 am
20276
... Have you tried chopping off the tops of the LEDs with a Dremel? That should give significantly broader coverage, no longer constrained to the 10 degree...
Ben Buxton
vk2xuf
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Mar 5, 2008
9:48 am
20277
... board. ... the ... You want to keep the 10 degree angle so the lines do not get undercut....
javaguy11111
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Mar 5, 2008
1:55 pm
20278
I have been fooling around with these UV LED's for several months by fits and starts. I bought a bunch from BestHongKong, and started out to use those, but...
pork_u_pine2000
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Mar 5, 2008
9:02 pm
20279
I did up a little program in scilab to add up contributions of a 1D array of LEDs based on the intensity diagram from the BestHongKong LEDs. You will have to...
javaguy11111
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Mar 6, 2008
5:09 am
20281
This question is suited for Electronics_101. http://groups.yahoo.com/group/Electronics_101 Thank you, Steve Greenfield owner Homebrew_PCBs and Electronics_101...
Steve
alienrelics
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Mar 6, 2008
3:29 pm
20282
Sorry, thought this was where people designed and built boards like this. ... worry ... [Non-text portions of this message have been removed]...
Jawa Lunk
jawa_lunk
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Mar 6, 2008
3:33 pm
20283
... .... Very interesting! I have had SciLab installed and wanted to do something useful with it for a while, so I just opened it up and dropped in the code...
pork_u_pine2000
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Mar 6, 2008
7:22 pm
20285
... That 2" was just minimum distance from what I observed to look 'fairly' uniform. I had a quick look at you model and it seems valid to me. I'm a bit of a...
Adam Seychell
a_seychell
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Mar 6, 2008
9:05 pm
20286
This is where you get help designing or making the PCB. Elecronics_101 is where you get help designing the circuit, which is what you need first. No big deal. ...
Steve
alienrelics
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Mar 6, 2008
11:20 pm
20287
Many of the of "professional" lab/prototyping PCB exposure units seem to be fitted with a vacuum assisted frame. I'm wondering if vacuum has much advantage...
Adam Seychell
a_seychell
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Mar 7, 2008
11:02 am
20288
Vacuum allows you to expose both sides at once, foam does not. ST...
Stefan Trethan
stefan_trethan
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Mar 7, 2008
12:08 pm
20289
I'm modifying an Epson Picturemate 200 for direct toner transfer, and I have a couple of questions about the ink cartridge that I hope someone can answer. The...
Mark Lerman
mark_from_po...
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Mar 8, 2008
7:58 pm
20290
Whoops - there are 7 contact....
Mark Lerman
mark_from_po...
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Mar 8, 2008
8:01 pm
20291
... Very hard to do with an inkjet printer, I'd imagine. -- Cheers Derryck...
Derryck Croker
derryck_croker
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Mar 9, 2008
11:52 am
20292
It's been done before - see the links for this group. I think it will provide the best resolution short of photographic techniques. From what I now have found...
mlerman@...
mark_from_po...
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Mar 9, 2008
2:24 pm
20293
Prior to advancing to this site you should check out http://tech.groups.yahoo.com/group/electronic_prototypes/ It may help you get to the point to advance to...
Brian
blue_eagle74
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Mar 10, 2008
12:56 am
20294
I would not bother to sign up for this group. There is not very much information and most of the messages are spam. Appears to be a "come on" to sign up for...
William Nelson
wnnelson0
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Mar 10, 2008
1:10 am
20295
It is important to use the correct terms, I'm not trying to be retentive. That is an inkjet and so uses ink, not toner. I don't know if that's the best printer...
Steve
alienrelics
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Mar 10, 2008
5:27 am
20296
So... people should leave this group and join yours? I don't see why that is necessary. This group is for all experience levels. I see this as splitting the...
Steve
alienrelics
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Mar 10, 2008
5:39 am
Messages 20265 - 20296 of 23865   Oldest  |  < Older  |  Newer >  |  Newest
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