Re: gEDA-user: OT: Bike Alarms
Q?. Do you want to protect YOUR bike or do you want to make a product? If you are making a product it does not matter HOW flawed it is. If it can be found and disabled, if it worked effectively or not. All these things are unimportant. Good marketing spin can convince idiots with expensive carbon fiber bikes they need the unit and it works brilliantly. If you make the successful product you will have enough money to buy lots of bikes when yours does get stolen and you don't care that it doesn't work. IF you want to protect your bike then think security through obscurity. I would not go bragging to anyone about my bikes security measures ;) ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: FT232R
William Estrada wrote: Hi group, Does anyone have a sym file for the FT232RL? http://www.gedasymbols.org/user/andrew_mccubbin/ But I might have horrible symbol styles I learned from Autotrax that others dont like. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Putting holes in hard steel - was - Re: the joy and sadness of new boards
If anybody has a better idea, yelp. EDM ? ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: the joy and sadness of new boards
DJ Delorie wrote: I think you can score them with a utility knife on both sides and snap them apart. I've tried that before with no luck. The boards are just too thick to be able to score reliably and deeply enough. That old wives tale comes from the days when paper/phenolic boards where the norm. Does not work on FR4 ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: electrolytic capacitors
Someone wrote: [Electrolytics] can explode pretty violently, so let me tell you a story. [...785V on a 450v cap...serious dent in plaster...] Robas, Teodor wrote: SNIP The resulting flame was always entertaining ! Sometimes the ASIC wanted to take all the punch and dig a hole the size of a finger in a 4 layer PCB. The capacitor, only 220uF/50V, survived. I will second the silicon and epoxy makes a more impressive explosion than electro/tants theory The one I remember is a TO-220 fet. I was at a place that made and fixed power inverters ranging from 12VDC-240VAC units for running a TV up to 110VDC-415VAC as UPS units for small hospitals. Behind the shed where the units where tested and fixed was a bank of lead acid cells. These cells were the normal 2V very many hundred amp hour cells used in solar RAPS. The battery that was made from them had multiple taps on it 12v 24v 48v 110v obviously for testing different voltage inverters. One day the guy was testing a 12V unit that used 50N05 fets. No prizes for guessing which tap he mistakenly used instead of the 12V one. Anyways - there was 110V across the FETs that are rated to half that. The big lead acid batteries that could make fencing wire do a good impression of a light bulb. The test did not last long. Two legs of the TO-220 package stayed in the PCB. Most of the epoxy gone. The metal tab of the TO-220 embedded 10mm into a besser brick (breeze block) wall 1/2 a meter behind the unit. I was five meters away and had ringing ears. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: best ways to do SMT assembly
David SMITH wrote: On Fri, Aug 15, 2008 at 09:43:33AM +0100, Dylan Smith wrote: On Thu, 14 Aug 2008, Robert Butts wrote: I got pcbs back and now want to assemble them. What is the best way, i.e. solder paste to use, heating method, solder bridge removal...? Most of the components are small SMT parts. The through hole parts I'm fine with. It depends what I'm doing. For discrete components (like 0603 sized Rs and Cs), just a fine tip soldering iron and fine solder wire - what I do is melt a small amount of solder on one pad, get the part with the tweezers, re-melt it and stick the end of the part into the molten blob. Then just solder the other end as normal. I can do this quite quickly. This is similar to the technique I use (although I don't go smaller than 0805). However, rather than use tweezers, I prefer to put the component onto the board, and then push it around using my fingernail on the top of the component, about half-way between the two soldering ends. I find that this gives a lot more control than tweezers. Of course, my version needs a bit more planning, as I need to make sure I've let my fingernails grow longer than normal to stop my fingers getting burned ;-) Try using Blu-Tak instead of either tweezers or finger nails. It is more compliant than either and doesn't hurt when burnt :D ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: best ways to do SMT assembly
David SMITH wrote: On Fri, Aug 15, 2008 at 07:12:14PM +1000, andrewm wrote: Try using Blu-Tak instead of either tweezers or finger nails. It is more compliant than either and doesn't hurt when burnt :D You mean to stick them to the board? Seems like a lot more hassle to have to stick the parts down first, rather than just push them into place. No - you use the blu-tak like the tweezers or your fingernail. Roll a small amount of it to a fine point. Use this point as a poker to move around the component like your fingernail. Push down on top of the component and the tacky properties of the blu-tak will allow it to pick up the component (like tweezers). Once one side of the component is soldered - just pull it off. Huge advantage over tweezers is that it is compliant. So it is easier to get the component to lay flat on the board. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Frontpast
DJ Delorie wrote: I usually put packing tape on the back to keep it from etching, but I float it anyway. I've tried lining up the two sides but lining them up is tricky. DJ, Now you have Seen-The-Light (tm) and come over to the side of photo-etch have you tried either the brass or alfoil stencil ? ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: 3D Falcon feedback mouse?
Jesse Gordon wrote: I'm still looking for a good quality but small USB camera (low-res black and white or high-res color prefered) that works with Linux, that is not ov511 based, if anyone knows of such a thing. (The ov511 works great, but has a bug which causes the auto light gain control to get stuck with the brightness turned all the way up.) A good old BT848 and a CCIR black and white camera would be very linux freindly and then you have much choice in camera. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: [pcb] overlapping pin/pad -- won't form thermal
Dave wrote: I realize I can draw them in by hand by turning of new traces clear polygons. I guess for this design that's what I'll have to do, because regenerating all my footprints, regenerating and re-validating the net list, and re-doing all the routing done so far is just too costly. That is how I do it. It upsets me that oblong pads are not supported well as I love them for home made boards. If I was bright enough to write C code I would try change it seems well beyond me at present. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: wacky (or not?) solder stencil ideas
Dave wrote: SNIP and paint both sides with machinists' blue stuff -- I'm not sure what it's properly called Prussian Blue. Though not the neo-nazi/white-power rock band. SNIP The CO2 laser is the wrong wavelength for cutting metal, it just reflects off.) The CO2 laser will cut metals. Just not ones like copper and brass. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: geda tarball
Give me a couple of days, and I'll send you some un-official 1.3.1 .debs if you want to try running latest gEDA, with icons etc... (This is if you don't mind beta-testing for us). I use a vanilla debian install and am happy to help with testing. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: geda tarball
Peter Clifton wrote: On Tue, 2008-01-15 at 08:39 +1000, andrewm wrote: I use a vanilla debian install and am happy to help with testing. As I'm using Ubuntu Gutsy, I'm not able to provide Debian packages. If you wanted to build from source, there can be found here: http://geda.seul.org/sources.html Oops, Sorry - I thought the discussion was about Debian. I already have built from source. Was just offering to help testing a packaged version. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: anyone has had success with 0.2mm?
Lope De Vega wrote: SNIP I'm trying to build a circuit with a cp2102, which has 0.5 mm between pins' center (actually 0.2mm between pins). It is a qfn-28 package. I wanted to ask if anyone has had success with something similiar? my workflow would be printing the schematics as given by pcb in hq paper, and then transferring them with the iron onto the pcb, as I have't got any sort of specialized equipment, I'm just a novice. Regards, Not toner transfer but Kinsten brand thin substrate photo boards http://www.thehacktory.com/Simple-IR-RX-Prototype-V1p4-Top.jpg 0.45mm pitch 28pin QFN package with a exposed paddle. So it is quite doable at home. The hardest part is the 0.3mm vias in a drill press with no alignment aids. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: anyone has had success with 0.2mm?
DJ Delorie wrote: The hardest part is the 0.3mm vias in a drill press with no alignment aids. http://www.delorie.com/pcb/dremel-stand/ although the dremel shaft itself has about 6 mil of play in it. I've tweaked the drill helper checkbox of the PS exporter to be more suitable for this particular use; in addition, using a pushpin or other sharp metal object, you can pre-poke the right spot and the dremel will wander into it when you drill. I can reliably drill 13.5 mil vias with a 9 mil annulus. http://www.rejon.co.uk/manix_md1h.html Is the little guy I use. The 12K RPM is a bit low for 0.3mm but it is nice in terms of runout/wobble. I want to build my own spindle/BLDC one day when I have time so I can spin the bits and an appropriate speed. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Ok, who moved pin 4?
Google PCB under a windows machine Fist hit Wikipedia Polychloride Biphenyl Second Hit Wikipedia Printed Circuit Board Third Hit pcb.sourceforge .net Peter Clifton wrote: On Mon, 2007-11-26 at 15:02 -0600, John Griessen wrote: Peter Clifton wrote: Perhaps we should namespace pcb as x-geda-pcb ? (Just x-pcb seems like its more likely to clash with other things.) Nah, pcb was first, and deserves the broad name -- like .com's popularity compared to .biz. I was going to say PCB's name makes it very hard to find amongst the other layout software out there.. but a quick check (before making that assertion) reveals us as No.3 in the Google listings. I'd love to see if a Google search for pcb from a non linux user with a Windows browser shows the same listing... I get the strong suspicion some search just come up too nerdy from my computer _not_ to be special cased against Linux / my search history. Best wishes, ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Enlarged footprints for hand soldering -- name conventions
I asked the same question a few months ago and didn't think the Nominal/Maximal/Least names where suitable for my hand soldered footprints. For the hand soldered footprints the pads extend way past what is in the maximal JDEC footprint. I decided to just postscript HS onto the end of the footprint and keep them to myself so as to not confuse other people. Kai-Martin Knaak wrote: On Tue, 20 Nov 2007 13:58:02 -0500, DJ Delorie wrote: M for maximum pads, and L for least pads. Why didn't they go in line with the common T-Shirt sizes: S = small, M = medium, L = large, XL = extra large ... ---(kaimartin)--- ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: ping 2
Greg Cunningham wrote: On Sat, 2007-09-29 at 02:31 -0400, Dave McGuire wrote: On Sep 29, 2007, at 2:29 AM, Greg Cunningham wrote: Please excuse the QRM. testing new MTA Nope, it's broke. ;) -Dave My!... Early riser in Florida? ..or are you up watching the AFL (Australian Rules footie) grand final? No one is watching the AFL grand final. They are getting all rested up waiting for the real football grand final :D ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: ping 2
Dave McGuire wrote: On Sep 29, 2007, at 2:54 AM, andrewm wrote: Please excuse the QRM. testing new MTA Nope, it's broke. ;) My!... Early riser in Florida? ..or are you up watching the AFL (Australian Rules footie) grand final? No one is watching the AFL grand final. They are getting all rested up waiting for the real football grand final :D ...while some of us are doing other stuff while wondering why some people like to watch grown men chase a ball around in the grass! ;) -Dave Don't watch it myself either. However it is a long standing tradition in the northern states (QLD, NSW) to use the words real football in reference to rugby when ever someone mentions aerial ping pong. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Idiot with problem - was - Re: pcb-20070912
I am trying to install the 20090912 version to check if bugs I am getting are new or fixed ones before I trouble the list with them. However I am not even bright enough to install the thing. I am on a debian etch box. I have make uninstall'ed stuarts ISO version. I have edited the Makefile in the new sources directory to be the same path name that the ISO version used. I run make install and after a while I get. configure: error: libgeda detection error: no package 'libgeda' found. So I make configure (with the prefix to my install directory) libgeda-1.1.2 Then I make install libgeda-1.1.2 and it does not report any errors. But when I try to make install geda-gschem-1.1.2 I get the same message as above. Can someone point out what stupid thing I have done wrong or am missing in the install instructions. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: First PCB
John Griessen wrote: I like your minimization of vias. Most of your vias seem to double as headers for test and interconnect. The only way I could work out how to do this easily in PCB was to make a new component that was just 5 pins in a row and add them in the schematic to the traces I knew where going to be the via/test points along the side. That is probably the nice way to do it and makes things more followable. In protel I just used to pop down vias and pads where ever I felt like it and it would let me connect them. http://www.thehacktory.com/IR-simple-schem.png The ones marked as GPIO1..3 are also the AVRs ISP pins so that I can get the infrared based bootloader in the chip when they are first put together. After that re-flashing of the chip does not need a connection. Seeing as it does not add any extra board space or weight I have left them for use as GPIO and also added 4 more pads on the other side to give access to 4 ADC pins in case anyone wants to use them. Looks good. Good use of space -- little waste, but not too crammed to be a practical test/eval/modular add-on board. I was actually cheating a little bit. This board was a redesign of my last board I ever made with protel. http://www.thehacktory.com/Simple-IR-RX-Prototype-V1p4-Bottom.jpg http://www.thehacktory.com/Simple-IR-RX-Prototype-V1p4-Top.jpg Protel for DOS used 1/1000th of an inch as its internal measurements. Made aligning things on 0.45mm pads a bit hard. So the ATMega48 in the photo is my reason for switching to PCB/gEDA. PS What's it look like if you run global puller on it? It took 10 minutes for the auto opitmizer to run and all it did was spread out a few of my manually added teardrops and pulled one track straight from GND to VCC to create a dead short. Ben Jackson wrote: If that big square is a thermal pad, it's not going to help much if you don't stitch it to more copper on the other side... The big square pad under the QFN28_4 is the extra GND pin for the ATMega48. The chip is only going to be pulling 0.5 to 1mA so should not need extra heatsinking. It does however help with noise performance to connect the pad to GND. The drain pad on the SC70-6-EP FET is being used as heat sink. And before I go into prod. I may try get more copper and vias around it for better heat dissipation. Though I am being very conservative with that FET. It is good for 5.5Amp and it is only going to be asked to do 0.5 to 1Amp in normal duty. Also, I think your attachments to the sides of those long, skinny pads might cause you grief if you don't have a soldermask. Yes - will have solder mask and paste stencil. John Griessen wrote: So, what is that under chip square of copper connected to two pads? A mini ground plane? http://www.thehacktory.com/datasheets/gp1us30xp_e.pdf Is the device. A 38KHz infrared receiver. The manufacturer recomends the GND pad underneath to help with noise performance. Coupled with the metal case on the top it forms a cage/box around the whole thing. I agree with the manufacture in this case. The receiver is very very sensitive to noise and you can gain/loose meters of range with out the GND. Careful placement of other noise on the boards and snuffing them can gain/loose you 10 meters range. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: First PCB
After much wailing and gnashing of teeth at the grid alignment bug here is my first PCB produced with gEDA/PCB http://www.thehacktory.com/IR-simple-v1p52-top.png http://www.thehacktory.com/IR-simple-v1p52-bot.png It took several days because of learning curve and the grid bug and there are still some chamfers I need to add and do a final check of the PCB in general. Hopefully PCB number 2 will not take as long. I will download new snapshot and see if the bug is gone and if not I will post a bug report. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Curious Behaviour
Guys, Don't know if this is a bug or not. I have a PCB that is metric grid of 0.05mm. I have my 0.45mm pitch QFN package all lined up on the grid so traces end on the pads. I make a component get too close to a via (purposefully to replicate the behavior) I do a DRC and it pops up the clearance error (highlighting it blue) My grid has been messed up and my traces no longer land on the 0.45mm pitch pads. I have to set the grid to imperial 0.1mil and select all components and move then a given amount to realign the grid. I googled a bit at http://archives.seul.org/geda/bug/ to see if anyone else had come across it but came up blank. Am I doing something wrong? It is very annoying having to re line up everything each time a DRC fails. (I am making a PCB that every 10th of a millimeter counts) ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: buzzing board
TOP POST - bad andrew Have you tried the contact microphone (pizeo buzzer) yet to narrow down the location ? Hook it up to your sound card if you don't have a great scope. I am assuming it is in the bottom right hand corner of the picture where it looks like the switcher and the SM inductors are that it seems to be coming from. Maybe you could consider one more culprit in that corner you may have over looked - the DC plug. DJ Delorie wrote: Ceramic caps on a switching power supply can have a pizeo eletric effect. Try poscaps or a tant. The switcher caps are tantalum. There are also two electrolytic bulk caps, one on each side of the switcher. Probably the best view of these is here: http://www.delorie.com/electronics/alarmclock/20070908-board.html The OLED's LDO is in the far upper right in that photo. For the purposes of solving this problem, I put the design files here: http://www.delorie.com/electronics/alarmclock/20070913-design.zip Did you cheap out on the inductor? Not that I'm aware of. I used these: 495-2003-1-ND EPCOS B82464A4104K (100uH) PCD2089CT-NDPanasonic ELL-5PM3R0N (3uH) ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: CuCl comments from a user - was - Re: PCM making methods - was - Re: alarm clock update
Tools, I use a car battery hygrometer for measuring density. The car battery hygrometers do not cover the full range of acceptable densities for etching but does cover the optimum. For acid measurements I do periodically titrate using the method given by Adam in his page. Most of the time I just add a dash of acid at the start of each session. (A pinch of salt, two cloves of garlic and splash of white wine) I bubble during etching and for a while afterwards to regenerate the mixture. Also my tank is about 5 times bigger than I would use if I was using FeCl. If you have a lot of spare etching capacity you wont ever run into copper saturation. The etchant does grow but very very slowly. In fact it does not grow fast enough for me to give it away. Most people I know want to start using it when they see it so I have to throw extra scrap copper in and bubble for days to get extra etchant to give away. (I am always titrate after eating a lot of copper to grow the bath) The air DOES regenerate it completly. You don't need to add H2O2. But I do keep some H2O2 spare in case I need to do a lot of etching at once. The H2O2 gives you an instant regeneration rather than having to wait hours. The etch rate I get is a little slower than FeCl3. However it does not give as good an edge as the FeCl. It gives as good a detail as H2O2/HCl or amonia persulphate. In my experience none of them compete with FeCl3 for resolution. If you run CuCl (or H2O2/HCl) at elevated temp then the speed can be better than FeCl3 but at the expense of more undercutting. I only run my etchant at 30 degrees C. At 40 degrees C (105F) I get a bit much fuming for my likeing (I probably keep it too green and too high in acid most the time) ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Text on silkscreen
My brain is getting a bit fried at the moment with new software overload. I am having an issue with silk screens on PCB. I can not turn off the silk screen legend (only switch between footprint refdes and value) and I also can not delete the text on the silk screen. I am making a board that is too small to have any silk screen at all and the silk screen text obscures the traces too much to make working easy. However if I turn of the silk screen completely (which I would prefer) I can not drag/move components. Is this normal behavior ? ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: buzzing board
DJ Delorie wrote: 1. How do you find out where such a noise is coming from, when everything is so close together? Neither a stethoscope nor a straw were helpful. Get an electret mic running off a battery on one scope lead Probe around with other scope lead to see what is in sync with it just to make sure you are looking at the right part of the circuit. You could spend ages looking at that switcher for the OLED and find out that the buzz was a slightly different frequency coming from somewehere else. Next you can get a peizo element and solder some whiskers to it and use that to probe components for the same noise. With contact from the whiskers you maybe able to track it down further than a straw/stethescope could 2. What kind of components *can* make that kind of noise? Anything from inductors and electro caps through to actual copper traces. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: buzzing board
DJ Delorie wrote: A lot of switching power supplies have a low-current mode where they don't switch at the full rate. It's switching at 150KHz (it's normal rate), about 25% duty cycle. I tried adding a 68 ohm resistor on the 3.3v bus, no change. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user So do OLED displays buzz themselves ? ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Text on silkscreen
DJ Delorie wrote: However if I turn of the silk screen completely (which I would prefer) I can not drag/move components. Is this normal behavior ? Yes. What I'd do is set the minimum silk to 0.1, and reduce the sizes of the text so that it *does* fit on your board. Then, when you make the board, just toss the silk layer away. I did my furnace board that way. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user Thanks. Bit of lateral thinking to the problem. That will teach me for looking for a menu option. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Request for comments
andrewm wrote: I have same numbered the pins on the switch as they are electrically connected inside. I often use the pins on those switches as jumpers to get wires out of tight spots and thought that giving them the same number would allow the nets to look connected. Steven Michalske wrote: From my experimentation, PCB wants the net connected to both of the pins and will not treat it as a jumper... I find this as a minor bug, would you care to verify and make an example schematic to submit a bug/feature request for us? Steve, Sure I can do a bug/feature request on this (after I read up how too). Just want to make sure that it is something wrong or something people want. Should the two pins same-named be treated as a single entity so they can be used like a jumper or should the connection have to be made manually in the schematic and the pins be named differently. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
John Griessen wrote: I'm liking the transparency and low hassle and low toxicity of HCl/H2O2, and mostly want to do prototypes or circutis that go on low cost substrates so don't need to be teeny as possible to save board area. I like the low tolerance approach -- don't want to be a commercial fab. I got pretty good results etching DJ's lines test pattern for choosing amount of bloat to use in making postscript masks. 8 or 9 mils was the limit with my laser printer and toner transfer. I didn't see much morphing of shapes from etching. I etched with good stirring action. My HCl/H2O2 recipe is: 250 ml 35% Hcl, 35% H2O2 500ml distilled water, do all the acid precautions, work under a shade tree, use 1000ml Erlenmeyer flask, add half the acid to the water, stir and add the rest slowly, heat on hot plate to 105 deg C, add 3 5 inch lengths 12 Ga Cu wire, stir occasionally till dissolved, Next add 20 ml of H2O2 and 40ml of HCl at a time according to appearance. Aim for yellow green solution, if blueish needs more HCl, add H2O2 carefully, and if you see bubbles starting to evolve much, stand back since it's chlorine. Now to use for etching, just observe colors: If dark and starting to be hard to see your board from too much dissolved copper, add some H2O2 to clarify. If getting to be forest green or blue green, it needs more HCl. The solution volume grows. Neutralizing with Na-OH gives copper oxide precipitate and fairly pure slightly salty water you can dump on the ground. That's what I like about it compared to FeCl. No bright orange stains (on everything), and easier to neutralize and the remains of neutralizing can be sold even. If you let the HCl H2O2 just keep going to emerald green you will get CuCl etchant. You never again need to add H2O2 and can regenrate it by bubbling air through it. I have been using CuCl for a bit over a year now and all I ever need to do is measure the acid levels and density and then top up with HCl or water to keep it in spec. Will still stain like FeCl, but you never need to neutralise it or throw anything away. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: PCM making methods - was - Re: alarm clock update
JohnG wrote: What do you all think about inkjetting of resists? The second biggest problem apparent with direct inkjet is pooling. The big problem is surely the ink not actually resisting. But pooling caused by too much ink in one spot while wet is causing uneven coverage and the thin areas wash away or crack. Filling all the carts with one colour and printing composite black will prob make that worse. Maybe one solution is to hack the printer or rewrite the driver to do single pixel bands with a few seconds between each pass to allow ink to dry. I never looked into it too much as I didnt find the other methods of making a PCB too painful. DJ Delorie wrote: In my case, since I was etching brass, I probably could have just run the brass through an unmodified printer. But getting the right inks and keeping the nozzles clean seems to be a tricky bit for them. Heck, I have a hard time keeping the nozzles clean with the original inks. DJ - When you are etching your brass stencils they are almost all resist and only tiny apatures. If you work out the cost of inkjet ink and the amount of coverage you need - it may make a $200K laser cutter seem like a prudent investment :D What I'm contemplating is switching to photoresist. You print the pattern on transparencies, photoexpose, develop, and etch. No laminating, soaking, etc. The advantage is that it's easy to line up transparencies because you can see through them, so doing double sided PCBs (or in this case, etch brass from both sides) is easier. YAY - another convert to photo :D. To be honest I have just bought some inkjet paper to re-try the toner transfer option. I was doing it 10-15 years ago using OHTs. The trannys gave beautiful results but where temperamental. The photo paper is quite reasonable in terms of quality and I may use it from time to time on single sided baords with 16/16 rules. I am going to stick to photo for the DS 6/6 stuff though. I might switch etchants to something see-through too, like the HCl/H2O2 mix. HCl/H2H2 (and the CuCl I use) do not give as sharp an edge as FeCl3. Also I think for your brass masks that HCl may not be the best solution. Check with someone smarter than me, but I think it is bad with brass. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: PCM making methods - was - Re: alarm clock update
andrewm wrote: DJ - When you are etching your brass stencils they are almost all resist and only tiny apatures. If you work out the cost of inkjet ink and the amount of coverage you need - it may make a $200K laser cutter seem like a prudent investment :D DJ Delorie wrote: SNIP But I use a laser *printer* not a laser *cutter*. Printing a page of mostly-black isn't that expensive. Yep - full coverage pages on a laser printer only work out $1 as opposed to inkies that are $5ish. The photo paper is quite reasonable in terms of quality and I may use it from time to time on single sided baords with 16/16 rules. I do 8/8 with TT but them I'm using the special paper that releases easily. I have inquired with pulsar about prices as I may start selling it on my web shop. If I get a reasonable response I may have a few 100 boxes of it sitting here soon. The test board I did with the generic inkjet photo paper was the 8/8 rule IR-RX I have posted pics of. The 8/8 rules came out OK in about 5 of the 12 PCBs on the panel. And the PCBs are only 8x14mm. So I think the chances of getting a large board working at 6/6 is pretty slim. I know I can do this easy with photo and FeCl (though not with CuCl) I am going to stick to photo for the DS 6/6 stuff though. The limiting factor (for me) for the TT is the quality of the edges. I haven't tried disableing REt though, it might be dithering the edges for me. Look at these photos. It is of a spiral/swirl test patter someone on homebrew PCB made up (Derrik maybe). http://www.thehacktory.com/LaserWide.jpg http://www.thehacktory.com/LaserClose.jpg It shows some macro shots of some lines that are somewhere between 4 and 6 thou. This shows how the toner particles scatter and make a fuzzy edge as opposed to a nice clean line. That is going to limit your res no matter what method you use a laser printer for (photo or transfer). The printout in the photo above was on a medium sized car priced laser printer. The little $2000 printer I have on my desk does worse than this. I assume that cheaper 1200dpi printers are even worse again. My old HP-LJ4 that was only 600dpi didnt suffer as much. I guess the toner particles where bigger and more controlable I think to get better resolution I should resurect my much stalled plotter project :( SNIP ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Request for comments
Howdy all, I have just uploaded my first footprints I have made to the geda symbols site http://www.gedasymbols.org/user/andrew_mccubbin/ If some of the in crowd can have a look at them and comment if I am doing things the right way. Hopefully before DJ links them to the front page and they escape to the real world. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Request for comments
andrewm [EMAIL PROTECTED] writes: If some of the in crowd can have a look at them and comment if I am doing things the right way. DJ Delorie wrote: Quick note: you shouldn't draw silk over pins or pads. Some fab houses won't remove it, resulting in ink on top of your exposed copper. Ah - OK - didn't realise not all fabs removed the silkscreen over pads. Will fix that up. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Request for comments
Ben Jackson wrote: Looking only at CTS-252-switch in detail: PCB will not clip the silkscreen over the copper, and some fabs will go ahead and print it right over the pads. Interesting quirk I see with PCB is that you have some same-numbered, overlapping pad/pins and they are in the same net (via 'find') but your same-numbered non-overlapping pins are not. I'm not sure how that would play out in a real layout. Your soldermask clearance is about 1.5mil. That's smaller than the printing tolerances of most fabs. On the other hand, if you grow all the soldermasks to some minimum after layout, starting small is fine. Thanks for comment. I did the 1.5mil clearance as that was the smallest of the common fabs I looked at on the internet and some of them said they automatically increase solder mask clearances if smaller than they recomended. I have same numbered the pins on the switch as they are electrically connected inside. I often use the pins on those switches as jumpers to get wires out of tight spots and thought that giving them the same number would allow the nets to look connected. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Marketing gEDA - was - Re: Professional PCB help using geda?
Duncan Drennan wrote: SNIP I think John Luciani has pretty much demonstrated that this is possible with a bit of work. All that now needs to happen is for people to start adopting gEDA - but that is a whole different story, which requires strong marketing. SNIP John Griessen wrote: SNIP I think marketing is needed to deal with the image oriented way most people function in the world. Such as asking for professional help. Help with an image. Without some kind of image creation effort on our part, we are left with the image of good luck...hah!, and we will be lucky to get even small engineering companies to adopt gEDA tools. SNIP I am excluding myself from the following collective question as I am only new here. But do the gEDA people in general WANT marketing to new users at the moment ? Do you think the gEDA suite is polished enough to keep newcomers happy. Are the experienced users going to get fed up with answering questions from new users? I am probably in a good position to push others in the direction of using gEDA but I am not sure how many people would take the push and not give up. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Footprint naming convention
John Luciani wrote: On 9/1/07, andrewm [EMAIL PROTECTED] wrote: I am presently drawing up footprints for my stock components. I have read the naming conventions for the footprints and have done some searches but can't find an answer to this query. I have for many components two different foot prints. I would like to know if there is a convention to naming the multiples. I don't mean I have a device that comes in a DIP40 and also comes in a TQFP44. I mean I wish to have two version of a MSSOP28W (0.65mm 28 lead 5.3mm wide package) footprint. I would like one version of the footprint following the manufacturer approved pin width/length. I would also like another version with longer pins that I use in prototype boards that I will hand solder. If you followed a manufacturer's specification I would use a suffix that calls out the specific manufacturer and package designation (e.g. __TI_DRC_Package) IPC-7351 calls out an environment use suffix which you could probably use for designating larger prototype pads. The Most Material condition may work for your prototype fooprints and the Nominal Material for a production process. M ... Most Material N ... Nominal Material L ... Least Material I am thinking of adding the suffixes MM, NM, LM to my naming convention to correspond to the IPC-7351 material conditions. (* jcl *) Thanks John, However the extra meat I put on some pads for prototype soldering is well in excess of the IPC-7351 most material. I think I will just pop a suffix on the back of them for my own use and I shall never release the footprints to not confuse others. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Footprint naming convention
I am presently drawing up footprints for my stock components. I have read the naming conventions for the footprints and have done some searches but can't find an answer to this query. I have for many components two different foot prints. I would like to know if there is a convention to naming the multiples. I don't mean I have a device that comes in a DIP40 and also comes in a TQFP44. I mean I wish to have two version of a MSSOP28W (0.65mm 28 lead 5.3mm wide package) footprint. I would like one version of the footprint following the manufacturer approved pin width/length. I would also like another version with longer pins that I use in prototype boards that I will hand solder. Any input on names appreciated. ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Units used by software
andrewm wrote: SNIP about metric footprints If it's not been done by anyone already I am going to just write some kind of parser that does it for me external. DJ Delorie wrote: Sounds like a useful tool. Teach it to allow overrides on a per-value basis (like my 2pad script does). I.e.: Pin[0.2 0.2 0.5 0.2 0.2 10mil 0.1] Hmm^2... teach pcb's parser to support a unit suffix on each value! We only need mil and mm, but the mechanism should allow for more as needed. It won't *save* that way, but it lets you read in footprints with human-simpler values. OK - well I am not very bright and the chances of me modifying the code tree for PCB without breaking something are slim to none. So I shall do it external. I will public the code, however I would have to prefix it with a warning that veiwing my C style may cause people to run away screaming my eyes my eyes. It really is that ugly. If no one has any better suggestions I am going to make it take one input file read-modify-write it. Any line in the file that has a dimension suffix it will comment out, add a comment line to say it is autogenerated and then put the computer readable centimil version. Eg. pin[0.2mm 0.2 0.5 0.2 0.2 10mil 0.1mm] in the file would end up #pin[0.2mm 0.2 0.5 0.2mm 0.2mm 10mil 0.1mm] # The following line was automatically generated pin[7874 7874 19685 7874 7874 1000 3937] That should mean that you can un-comment the old version and try again if you made a mistake. I will make it so that you only need to sufix the unit if it changes. In the example above only the first dimension had a sufix until the units changes at 10mil and then the next metric after that one needed a sufix again. Or is this getting to complex to document for people ? (it's trivial code wise but may cause headaches in terms of noob questions) Finaly any objections to mm = Millimeter um = Micrometer mil = thousanth of an inch cmil = 100 thousanth of an inch ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
gEDA-user: Units used by software. - was - Re: C++ (was Re: interesting links)
Someone wrote:
Something about using smaller units
andrewm wrote:
Whats the smallest thing people have had to deal
with so far then ?
DJ Delorie wrote:
I've done 01005 caps, which are 8 mils by 16 mils. PCB had no
problem with those. I've also done 0.4mm pitch VSSOPs, which
is about an 8 mil wide pad. I've not gone below 6 mil line/space
rules though.
So is there really a need to change the units used in the software
then ? I recently switched to gEDA from autotrax because I could
not line up a 0.45mm DFN package I am now using a lot. The 1E-5
units seem to be more than adequate for this.
Also on the same subject as units - I think it would be nice to be
able to enter units for foot prints in metric. Is this possible
anyway (I did not find refs to metric footprints). If it's not
been done by anyone already I am going to just write some kind
of parser that does it for me external. Might make it convert
units in {} as metric to [] inch units. It's a fairly trivial
grip I have there but all the little components are drawn in
metric now.
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Re: gEDA-user: C++ (was Re: interesting links)
DJ Delorie wrote: We're going to need to bump pcb's resolution up again. Steve Meier wrote: I have serious reasons to think so. Whats the smallest thing people have had to deal with so far then ? ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
