Re: UV LED Test
2008-03-05 by pork_u_pine2000
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
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Re: UV LED Test
2008-03-05 by javaguy11111
... board. ... the ... You want to keep the 10 degree angle so the lines do not get undercut.
Re: [Homebrew_PCBs] Re: UV LED Test
2008-03-05 by Ben Buxton
... 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
Re: UV LED Test
2008-03-05 by javaguy11111
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
Re: [Homebrew_PCBs] Re: UV LED Test
2008-03-05 by Adam Seychell
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
Re: UV LED Test
2008-03-04 by javaguy11111
... 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
Re: UV LED Test
2008-03-04 by javaguy11111
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
Re: [Homebrew_PCBs] Re: UV LED Test
2008-03-04 by DJ Delorie
... What if you built your exposure box with mirrors on the sides? It would appear to the pcb like an infinite grid of LEDs.
Re: [Homebrew_PCBs] Re: UV LED Test
2008-03-04 by Adam Seychell
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
Cheap laminator project
2008-03-03 by josemj1
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
Re: UV LED Test
2008-03-03 by javaguy11111
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
Re: [Homebrew_PCBs] Re: UV LED Test
2008-03-03 by Leon
... From: javaguy11111 To: Sent: Monday, March 03, 2008 2:12 PM Subject: [Homebrew_PCBs] Re: UV LED
Re: UV LED Test
2008-03-03 by javaguy11111
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
Re: [Homebrew_PCBs] Re: Altium
2008-03-01 by Dylan Smith
... 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
Re: Altium
2008-03-01 by logicresearch
Then again, if you look on the internet, there aremillions of freee copies .... ... have
Re: Banning members - technically not subject material but
2008-03-01 by Steve
If you reply from within the group, when you hit reply you have the option to change where it goes: the group, the poster, or the moderator address. Or just
Re: Small Quantities of Soldermask
2008-03-01 by javaguy11111
The solder mask is in. I also found Duponts datasheets for the photoresist and soldermask for those who are interested. The photoresist datasheet is at
UV LED Test
2008-03-01 by javaguy11111
I just did a quick test with my UV LEDs using a step pattern going from 10/10 spacing down to 1/1 spacing in thousands of an inch. This test pattern was
Re: Altium
2008-02-29 by furry_t_bear
... Steve, Please let me say that I, for one, applaud your move. I won t go on and on, but it was the right thing to do, for any number of reasons. Regards,
Banning members - technically not subject material but
2008-02-29 by SRY
... Not seeing a way to directly contact the moderator I ll simply suggest the following: It is true that Yahoogroups can delete a group IF someone complains
Re: Altium
2008-02-29 by Steve
I ve banned him for posting a product activation key. I ll not have this group destroyed. Draw your own conclusions as to how he got it for free. Steve
Re: Altium
2008-02-28 by logicresearch
Michael - can I email you outside yahoo somehow? Daryl. ... back. ... PC ... virus signature database 2901 (20080225) __________
Re: Reg keys and pirating will get you banned
2008-02-28 by Steve
Registration keys or activation codes. Quite a lot of software requires you to enter a string of alphanumeric characters in order to either unlock the
Re: Reg keys and pirating will get you banned
2008-02-28 by ic_eng
Wihout violating your rules, What are Reg keys , or what do they do ?? Alex, ic_eng
Reg keys and pirating will get you banned
2008-02-28 by Steve
I can t and won t try to control what you do off list. However, talk of pirating, warez, or posting of reg keys or where to get reg keys will get you banned
Re: Altium
2008-02-28 by Steve
Posting reg keys is grounds for banning. Steve Greenfield
Re: Altium
2008-02-28 by logicresearch
Lucky you - I have a copy of Altium 6.8.0.11816 already installed, I can get that for free, guess I just need the $10794.40 for the code to unlock it. ...
Re: [Homebrew_PCBs] UV LED + photoresist experiments
2008-02-28 by Leon
... From: agscal -AGSCalabrese To: Sent: Thursday, February 28, 2008 4:31 PM Subject: Re: [Homebrew_PCBs]
Re: [Homebrew_PCBs] UV LED + photoresist experiments
2008-02-28 by agscal -AGSCalabrese
I did not know that. Do you have a graph of wavelength vs transmssion % that I could be directed to ? Also, If the glass happens to have unsuspected
Re:Toner Transfer PCB Method
2008-02-28 by Matt Casey
Hi All, I m glad you found site useful. I ve been lurking in this group for a long time so I thought it was about time I gave something back. I think for me
Re: [Homebrew_PCBs] UV LED + photoresist experiments
2008-02-28 by Leon
... From: agscal -AGSCalabrese To: Sent: Thursday, February 28, 2008 5:54 AM Subject: Re: [Homebrew_PCBs]
Re: [Homebrew_PCBs] Re: UV LED + photoresist experiments
2008-02-28 by Adam Seychell
... I ve since been browsing the web and it appears manufactures of photoresist go to great efforts to try make their exposure a non-linear function of
Re: Toner Transfer PCB Method
2008-02-28 by Steve G4ZDU
... Thanks for the excellent description of your toner transfer method and photo s. I m sure given time I ll crack the process thoroughly. I m getting there
Re: [Homebrew_PCBs] UV LED + photoresist experiments
2008-02-28 by agscal -AGSCalabrese
You might want to find a way to lose the glass layer. It may be sucking UV energy or converting it. How about vacuum suction or really thin glass ( 1mm ) ?
Re: UV LED + photoresist experiments
2008-02-28 by javaguy11111
... unit. ... Definitely very peculiar. I would expect the exposure time to go up with the square of the distance. So a four times increase in distance would
Re: [Homebrew_PCBs] UV LED + photoresist experiments
2008-02-28 by Adam Seychell
... Yes, I tried 20mA at 120mm distance and still no exposure. I also tested 15mA at just 20mm distance and got complete polymerisation in under 2 minutes. So,
Re: [Homebrew_PCBs] UV LED + photoresist experiments
2008-02-28 by Russell Shaw
... Have you tried using the same higher current and just increasing the distance? Maybe the wavelength is increased at lower current, which would reduce the
Re: [Homebrew_PCBs] Re: dvd printer
2008-02-28 by Mark Lerman
I don t think so - the paper appears to come out the top. I m hoping its small size will allow easy modification. In any case, it s cheap since that model is
Re: dvd printer
2008-02-27 by rdheiliger
Is the PM200 a flat bed type printer. Could not tell from the pics on ebay. RD ... shipping. It s very high resolution with piezo print heads that prints 4x6
UV LED + photoresist experiments
2008-02-27 by Adam Seychell
I ve been experimenting with some UV LEDs for building an exposure unit. I m using the negative dry film photoresist and discovered to my surprise that there
Re: [Homebrew_PCBs] Re: Toner Transfer PCB Method
2008-02-27 by Myc Holmes
Nice write up! You have added one very improtant step, using a dowel to focus the pressure. Very clever. Myc ... [Non-text portions of this message have been
Re: Toner Transfer PCB Method
2008-02-27 by catmacey2
Hi Steve, I ve been having quite a bit of luck using toner transfer with simple sheets of magazine paper and an iron. All of the boards I ve made have been
Re: [Homebrew_PCBs] Re: dvd printer
2008-02-27 by mlerman@ix.netcom.com
I just boughty an Epson Picturemate PM200 on Ebay for $31 including shipping. It s very high resolution with piezo print heads that prints 4x6 photos. I m
Re: dvd printer
2008-02-26 by r_twiddy
Hi all. Right now, I am using some ideas I found on the internet, to modify a Epson C84 printer. They have suggested pigmented inks , which work in the
Solder paste and IPA
2008-02-26 by Leon
Someone (I think it was Stefan) recently mentioned using IPA to thin dried-out solder paste, and had problems with spattering which he thought was due to the
Re: [Homebrew_PCBs] Re: Altium
2008-02-26 by Michael J Wallace
$10 grand? good lord, glad i got mine free ... From: logicresearch To: Homebrew_PCBs@yahoogroups.com Sent: Monday, February 25, 2008 10:05 PM Subject:
Re: Altium
2008-02-26 by logicresearch
I ve just been quoted $9595 for standalone plus 20% for floating (????). I haven t yet tried gEDA/PCB - I ll google it and see what comes back. Altium sounds
Re: dvd printer
2008-02-26 by tsescrl
Hello, If you want to see all professional PCB fabrication steps, go to: http://saturnelectronics.com/tour.htm#.htm And take - video tour - Patrick
Re: [Homebrew_PCBs] dvd printer
2008-02-26 by Mark Lerman
I was thinking of using small registration pins for both the carrier and the boards - have to experiment a bit. Perhaps preheat the board some, but I m a
Re: [Homebrew_PCBs] dvd printer
2008-02-26 by Harvey White
... Afaik, yes. The issues are the type of printer, that it must be able to deal with a CD, and that the ink is relatively critical. Some people preheat the