Announcement

Collapse
No announcement yet.

Easy to use schematic maker software?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #46
    Yes - I decided against the programmable constant cathode bias because, even though the dissipation requirements were modest, it was going to be inside the chassis, with no fan planned, directly underneath the EL34's - and I wasn't sure if the box would fill up with heat or not. I was considering posting the other board for comment, but this was a thread about schematic drawing software. But it uses a similar design to what I'd posted before but driving a negative grid bias voltage instead of sinking the cathode current and holding it constant voltage. I was kinda bummed, because I was really curious to try it, but I was up against 1) getting rid of a handful of watts of heat in an unvented chassis, and 2) when I started considering source followers on the grids, the additional aggrevation plus the heat concern made me decide to ditch it. Some day I'd like to try it though.

    It basically takes that 0-5v programming voltage and turns it into 0 to -80v, but that fault line goes high whenever either bias voltage is more positive than 20v or so and shuts it down if the bias circuit isn't ready/working/blew fuse. The gate drive and bias control is basically the circuit gingertube posted in the AB2 grid stopper thread, with a PVI in the error circuit / gate drive for bias control.
    The prince and the count always insist on tubes being healthy before they're broken

    Comment


    • #47
      Originally posted by lowell View Post
      Dang. Sucks I tried expresspcb but their dang software expresssch (schematics) does not have an "export netlist" option. Stupid. It does kinda show you what needs to be connected if you link the schem and pcb, but what's the point if you can't export the net and have it all layout the pcb for you? Am I lazy? Seems everytime I wanna make some boards it takes days and days to get the layout right, and make the board. I guess the real hard part is a good layout. That's why I'd prefer the netlist export option.
      I use expressPCB sometimes, but any kind of layout work in their software suite is just frustrating. It's better than just using a drawing program to make the shapes, but not much. I use a real PCB layout program, then copy it into expresspcb to get their cheap threefer rate for a few quick boards sometimes.

      The concept of exporting a net to a PCB suite and having it lay out the board for you is reasonable for digital boards, but auto place and route isn't yet good enough for analog work, in general that I know of. The programs keep getting better, but I haven't seen a really good auto-place-and-route from schematic for analog yet. I've tried it a few times with a couple of different PCB suites, and it works out that I can do the layout faster by hand than the machine can do it, and achieve better layouts in terms of compactness, manufacturability and analog signal integrity. I'm sure this little bit of John-Henry-ism will disappear some day, but I haven't seen it yet and I do a lot of PCB work.

      Down at the bottom of this, I think that the overall quality of an analog layout resides in partly experience - which is easy to write into a program - but mostly the fact that a human can consider the signal level and purpose of each trace as it is laid and use that as a guide for part and trace placement. I suppose that an advanced layout package would let you input a schematic, a bill of materials (for footprints) and physical board parameters, then run a simulation of the pure circuit in the background while placing parts and laying traces, using the physical placement and trace runs to then add the parasitics of capacitive feedthrough, magnetic field feedthrough, and trace resistance to get projected actual circuit performance as it goes.

      Now that I think of it, that's actually a good way to design a next-generation layout suite, since most new work starts as a simulation anyway. Running the simulation simultaneously with auto place and auto route and adding in calculated parasitics as the parts go down on the board out of the ideal schematic space would result in good layouts. It's a huge calculation problem, but we are in an era where we can all of us have several supercomputers at our disposal, and cheaply. I take that back - it's a monstrous calculation problem. It's probably more complex than playing chess, given that there are multitudes of acceptable outcomes, and each set of calculations has to stop when it's "good enough".

      I probably should never have taken those design automation courses. They're coming back to haunt me.
      Amazing!! Who would ever have guessed that someone who villified the evil rich people would begin happily accepting their millions in speaking fees!

      Oh, wait! That sounds familiar, somehow.

      Comment


      • #48
        Originally posted by jazbo8 View Post
        JSchem is cross-platform.
        'nother vote for JSchem
        Building a better world (one tube amp at a time)

        "I have never had to invoke a formula to fight oscillation in a guitar amp."- Enzo

        Comment


        • #49
          Hi Folks
          Ive been browsing this thread and I wondered if anyone has come across
          DESIGNSPARK PCB. I've been using it for about 12 months and it seems OK
          Quite straight forward to use and produces fair PCBs
          Here's a link to the website
          DesignSpark - Home » DesignSpark

          Comment


          • #50
            Since only a handful of people likely understood 'similar results', I wasn't claiming it would have the same impact as RG's now classic article, but rather that it would drive all the swine mad, to the point of running off a cliff in their frenzy.

            Gschem is a little more user friendly than the gEDA projects PCB (which could probably be more poorly named only if they had decided to call it "the" or "it") but it is usable once you get the hang of it. All of these programs have a bit of a learning curve. At times PCB reminds me of Xfig in terms of the GUI, ick.
            Last edited by NateS; 11-09-2012, 10:10 PM.
            The prince and the count always insist on tubes being healthy before they're broken

            Comment


            • #51
              Dave H, does freepcb do a decent job converting the netlist into a good layout and compact layout? Seems that the weakness trend here is exactly that when it comes to netlist export auto layout.

              Comment


              • #52
                Originally posted by lowell View Post
                Dave H, does freepcb do a decent job converting the netlist into a good layout and compact layout? Seems that the weakness trend here is exactly that when it comes to netlist export auto layout.
                FreeRouter can be used with FreePcb but I haven’t tried it. Even when using expensive pcb layout packages I prefer to place and route myself. I’ve only used auto routing a couple of times for memory boards.

                I’ve just tried FreeRouter. I un-routed a small FreePcb design and then auto routed it with FreeRouter. It did it OK with no failures.

                Comment


                • #53
                  Originally posted by Dave H View Post
                  I’ve just tried FreeRouter. I un-routed a small FreePcb design and then auto routed it with FreeRouter. It did it OK with no failures.
                  The manual and auto routed boards are below but which is which?

                  Click image for larger version

Name:	manual.JPG
Views:	1
Size:	210.1 KB
ID:	827427 Click image for larger version

Name:	auto.JPG
Views:	1
Size:	205.8 KB
ID:	827428

                  Comment


                  • #54
                    I was ready to try FreePCB, but I don't like the display. You can only see the layer that is on top. If a trace on the top layer overlays one on the bottom layer, the one on the bottom layer is hidden. With translucent colors you get a third color where traces overlay. Example: Red over Blue makes purple.

                    I used Tango years ago and it did what I like if I remember right. Correct me if I'm wrong J M.
                    WARNING! Musical Instrument amplifiers contain lethal voltages and can retain them even when unplugged. Refer service to qualified personnel.
                    REMEMBER: Everybody knows that smokin' ain't allowed in school !

                    Comment


                    • #55
                      Originally posted by Dave H View Post
                      The manual and auto routed boards are below but which is which?

                      [ATTACH=CONFIG]20945[/ATTACH] [ATTACH=CONFIG]20946[/ATTACH]
                      Easy, the left one is manual routed, the right one is automatic.
                      Both might be equally functional, though.
                      Juan Manuel Fahey

                      Comment


                      • #56
                        Originally posted by loudthud View Post
                        I was ready to try FreePCB, but I don't like the display. You can only see the layer that is on top. If a trace on the top layer overlays one on the bottom layer, the one on the bottom layer is hidden. With translucent colors you get a third color where traces overlay. Example: Red over Blue makes purple.

                        I used Tango years ago and it did what I like if I remember right. Correct me if I'm wrong J M.
                        Just checked.
                        Tango (I tried an old and a new version) shows opaque colors, the one you select in front fully hides the back one(s).
                        But then I tried Kicad (which I don't use yet but so far will be my next one) and it does.
                        A Red front track and a Green back one (who chooses such colors?) clearly show the yellow superimposed image.
                        Very easy to follow.
                        As I said, I'd love to standardize on Kicad, which is as free as "PCB" but approaches Eagle functionality.
                        The one I have seems to have only 2 copper layers (unless I set it up wrong) but that's more than fine with me.
                        Juan Manuel Fahey

                        Comment


                        • #57
                          Originally posted by loudthud View Post
                          I was ready to try FreePCB, but I don't like the display. You can only see the layer that is on top. If a trace on the top layer overlays one on the bottom layer, the one on the bottom layer is hidden. With translucent colors you get a third color where traces overlay. Example: Red over Blue makes purple.

                          I used Tango years ago and it did what I like if I remember right. Correct me if I'm wrong J M.
                          Just checked.
                          Tango (I tried an old and a new version) shows opaque colors, the one you select in front fully hides the back one(s).
                          But then I tried Kicad (which I don't use yet but so far will be my next one) and it does.
                          A Red front track and a Green back one (who chooses such colors?) clearly show the yellow superimposed image.
                          Very easy to follow.
                          As I said, I'd love to standardize on Kicad, which is as free as "PCB" but approaches Eagle functionality.
                          The one I have seems to have only 2 copper layers (unless I set it up wrong) but that's more than fine with me.
                          Click image for larger version

Name:	KiCadColors.gif
Views:	1
Size:	42.7 KB
ID:	827431
                          Juan Manuel Fahey

                          Comment


                          • #58
                            I've used FreePCB for what must be now a decade and it works swell for me. I've made hundreds of layouts with it and have not had any problems at all. I just type up a .net file on my wordprocessor, create any outlines I don't already have and import it. It exports all the Gerber files and Excellon drill file which I further process with Viewmate. Lately I've just been using AutoCAD to do the PCB layouts and print them on transparency then etch and drill up what I need rather than making a small run at a board house... saves me a lot of money doing it that seat of the pants way. I've recently tried out ExpressPCB and it looks to work nice but I probably wont be using it because my manual AutoCAD approach fits so nicely into my solids modeling I do for all my builds. I like to make it first in the computer before ever drilling, etching or soldering anything together... what do they say? measure twice and cut once.
                            ... That's $1.00 for the chalk mark and $49,999.00 for knowing where to put it!

                            Comment


                            • #59
                              Originally posted by Sowhat View Post
                              I've used FreePCB for what must be now a decade and it works swell for me. I've made hundreds of layouts with it and have not had any problems at all. I just type up a .net file on my wordprocessor, create any outlines I don't already have and import it. It exports all the Gerber files and Excellon drill file which I further process with Viewmate. Lately I've just been using AutoCAD to do the PCB layouts and print them on transparency then etch and drill up what I need rather than making a small run at a board house... saves me a lot of money doing it that seat of the pants way. I've recently tried out ExpressPCB and it looks to work nice but I probably wont be using it because my manual AutoCAD approach fits so nicely into my solids modeling I do for all my builds. I like to make it first in the computer before ever drilling, etching or soldering anything together... what do they say? measure twice and cut once.
                              "I've used FreePCB for what must be now a decade and it works swell for me."

                              AND for the last 10 years, there's a guy in Beijing, who has watched everything you typed on your computer, and has copies of all your PCB designs...he has all your banking passwords, and personal information.
                              No matter how many times we tell people that "free" stuff from the internet isn't "free," they just keep on installing it.

                              Comment


                              • #60
                                And not only "Free" software !!
                                There's a Software Company in Redmond, Washington, which *also* has watched everything we all typed on our computers, including copies of *everything*... has all our banking passwords, and personal information (including soundguruman's, of course) .... and to add insult to injury, charges for it .
                                So what?
                                Tell me something I didn't already know.
                                The only "safe" computer is the one which is *not* connected to the Internet, nor shares pendrives and such (or worse, LAN) with others which are.

                                PS: said Redmond Company, in fact, is doing that at this very moment.
                                PS2: have you *ever* read your own Register?
                                Don't you know it's regularly scanned and "interesting" information is uploaded all the time?
                                Juan Manuel Fahey

                                Comment

                                Working...
                                X