Re: gEDA-user: OT: help needed; asymmetric load after rectifier seems to disrupt its working.
What is the purpose of C1 and L1? If you want to filter anything, it should be AFTER you rectify the signal to DC. A series cap is going to remove low frequencies... like DC which is attenuated very highly. So much in fact that you can't draw a DC signal through a capacitor. That is why your circuit is not working. If you remove C1 and L1 the circuit will work the way you want it to I believe. Also, with an input frequency of 15 kHz or higher, you won't be needing 100 uF output filter capacitors for a light load. How many mA is your load? How much ripple can you allow? Use those two values to calculate the value of output filter capacitor you need. Once I fix your circuit by removing the input filter I measure 19.14 volts out and 38.2 mA of current into a 500 ohm load. Is that what you are shooting for? The 100 uF cap gives around 10 mV of ripple. With lighter loads or more ripple the cap can be smaller. Rick On 6/17/2011 4:44 AM, myken wrote: Yeap, it should be a very low power power supply. Vx is not important Vcc and Vss are. Vin can be anything from 15Khz to 28Khz so a transformer is not the most desired option. I have designed two SMPS for Vcc and Vss but there load to the rectifier are not the same, with the described result. I will try the options suggested in this list today. Robert. On 17/06/11 04:13, gene glick wrote: On 06/16/2011 02:30 PM, myken wrote: Hello all, I would appreciate some expert advice. Are you trying to make a low current power supply? I agree with DJ - the unequal loading on + and - cycle will average to something other than zero (unequal capacitors, unequal diodes, etc) If Vx must always be average zero - you'll need to do something else. If you can handle a little voltage drop, don't care what happens to Vx, and don't mind adding a few parts, make a cheapo regulator with a zener and BJT? (Or maybe use TL31 instead of zener) What about a small transformer, one winding on primary, center tapped on secondary. Add a diode and a cap for each leg - and there you go! Anyway, there's lots of ways to do this. If regulated output is what you want, a little more work is required. gene ___ 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
Re: gEDA-user: gschem saving symbols
On Jun 16, 2011, at 11:17 PM, Josh Jordan wrote: The plan is to add a 'Save symbol instance as...' to the right-click menu. It will open the file chooser in the directory of the original symbol and load file name from device attribute. I like this, although it's not so terribly difficult to get the same effect with a little planning. Sometimes the design drags you away from the plan ;-) Saving a schematic uses f_save in libgeda, I am adding a f_save_symbol. First I loop selected objects stopping at the first complex obj. Then get the text of the symbol with o_save_objects(toplevel, s_object-complex-prim_objs, 0); This returns almost the text needed to create the symbol file. The position of all the objects in the symbol are big numbers for the position they had in the schematic. Is there a reason to make these numbers small near the origin like in the original symbol file? Yes, for reasons Kai-Martin said. This shouldn't be too difficult to fix, since you've already managed to penetrate the obscure code here (good job!). There must be somewhere that the offset of the symbol within the schematic is stored (it's needed to generate the C record in the schematic file). Subtract that from the coordinates in the instance to make a proper sym file. John Doty Noqsi Aerospace, Ltd. http://www.noqsi.com/ j...@noqsi.com ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Documentation for scheme API
On 06/18/2011 03:00:20 PM, Peter TB Brett wrote: 1) API documentation sources *must* be in the same repository as the code, so that a single commit that changes the behaviour the unit tests also updates the docs. This is *essential*. Sure. However, this is no contradiction to using dokuwiki. See my previous post. 2) The gEDA wiki continues to be hideous and unnavigable, Like I said before, this is in no way an inherent property of wiki style software, or dokuwiki in particular. See my wiki at bibo.iqo.uni-hannover.de or any of the examples offered at http://www.dokuwiki.org/Template I volunteered to morph the look and feel of the geda wiki into something more usable. The response by the geda devs was nil. Yes, this put me off. Moving the documentation from being in-tree to a separate wiki is still a decision that I completely fail to comprehend. Why not reclaim it by putting the documentation part of the homepage under git control of the respective source? 3) Just to be make it entirely clear: we're not talking about the whole project documentation here, we're talking about API documentation that will be only of interest to potential developers. The C API docs aren't on the wiki: why should the Scheme API docs be? Because it lowers the barrier to contribute for everyone. And because it blends perfectly into the rest of the geda website. It is a widely used mark-up system. Comprehensive online help mailing lists and even an IRC channel is available. I'm not any sort of guru at Dokuwiki I wouldn't call myself a guru, either. But I sure am an experienced dokuwiki admin who knows, what can be done easily. and neither do I have access to configure the server, so expecting me to fix these issues is not realistic. Neither does Ales have time to do so, as far as I can tell. Then delegate the task to someone else. Has there been any effort to try and find a dedicated admin for the website? At the moment, I can either spend hours (more likely days or weeks) fighting the wiki, No need. Basic dokuwiki mark-up is straight forward and pretty simple. See http://www.dokuwiki.org/syntax If you want something more fancy like e.g syntax highlighted code snippets, chances are that there is a plug-in available. If you want to see how the mark-up is rendered: 1) install dokuwiki (is included in every major distro) 2) let a symlink in /var/lib/dokuwiki/data/pages/ point to the directory where your documentation sits. 3) point your www browser to http://localhost/dokuwiki.php Does that sound like weeks of fighting? It certainly wasn't to me, when I started with dokuwiki years ago. and spend the rest of time writing documentation. Dokuwiki is not a viable option. Well, it is not because you don't like it. Since you are the author, this is a perfectly valid reason. BTW, I am glad the lack of scheme api documentation is about to be relieved. ---)kaimartin(--- -- Kai-Martin Knaak Email: k...@familieknaak.de Öffentlicher PGP-Schlüssel: http://pool.sks-keyservers.net:11371/pks/lookup?search=0x6C0B9F53 ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: first time
kqt4a...@comcast.net wrote: I am duplicating a schematic just for practice I selected inductor-1.sym from Basic Devices and noticed it has no footprint The default library is notorious for not including footprint attributes to its symbols. This dates back to a emotional debate more than five years ago on how ideal symbols should look like. See the FAQ for details. http://geda.seul.org/wiki/geda:faq-gschem#what_s_this_business_about_heavy_vs_light_symbols The default lib has seen no substantial changes since then. Instead, a site called http://gedasymbols.org was introduced, where users can submit their symbols for public access. Lately, there is an effort to revamp the default lib of symbols and footprints. But don't hold your breath. Where do I find the footprint to add to this device 1) Locate the data sheet of your inductor and look for the proposed footprint geometry. 2a) start pcb, type [i] to open the footprint chooser. Flip through the footprint to find something that fits your inductor component. 2b) go to http://gedasymbols.org and look for a footprint that fits. Maybe you are lucky and somebody already uploaded a footprint specific component. 2c) roll your own footprint. More details at: http://geda.seul.org/wiki/geda:pcb_tips#i_want_to_use_pcb_to_do_layout_how_do_i_know_what_va lue_to_use_for_the_footprint_attribute ---)kaimartin(--- -- Kai-Martin Knaak Email: k...@familieknaak.de Öffentlicher PGP-Schlüssel: http://pool.sks-keyservers.net:11371/pks/lookup?search=0x6C0B9F53 ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: Documentation for scheme API
[snip] Like I said before, this is in no way an inherent property of wiki style software, or dokuwiki in particular. See my wiki at bibo.iqo.uni-hannover.de or any of the examples offered at http://www.dokuwiki.org/Template I volunteered to morph the look and feel of the geda wiki into something more usable. The response by the geda devs was nil. Yes, this put me off. Kai-Martin Knaak, you do not have to ask permission to do something like that. Please create/setup a better gEDA wiki on one of your 'net servers, advertise it (like here), and get people to add content to it. I can pretty much guarantee that if you create something superior, the existing gEDA wiki will become obsolete/out-of-date and nobody will use it. Please send out a link when you have something to show us. Thanks! -Ales ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
Re: gEDA-user: first time
[snip] Lately, there is an effort to revamp the default lib of symbols and footprints. But don't hold your breath. Kai-Martin Knaak, how is that new/revamped library coming along? Recall that in [1] you were challanged (and you accepted) to create a new default lib that can replace the existing shipping symbols library with something that is better. Everybody is waiting with bated breath! :) Thanks, -Ales [1] http://archives.seul.org/geda/user/May-2011/msg00441.html ___ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
