How do you design these days?
in [Design]
|
From: Joerg on 9 Jan 2010 12:39 JosephKK wrote: > On Fri, 08 Jan 2010 10:25:16 -0800, Joerg <invalid(a)invalid.invalid> wrote: > >> JosephKK wrote: >>> On Thu, 07 Jan 2010 08:04:12 -0800, Joerg <invalid(a)invalid.invalid> wrote: >>> >>>> JosephKK wrote: >>>>> On Sat, 02 Jan 2010 07:30:07 -0800, Joerg <invalid(a)invalid.invalid> wrote: >>>>> >>>>>> RogerN wrote: >>>>>>> Thanks for the replies, looks like mostly surf boards and dead bug for the >>>>>>> breadboard testing. >>>>>>> >>>>>>> I see that for many designs you go straight to the board, any recommended >>>>>>> software for hobbiest budget. LT Spice and Eagle perhaps? ... >>>>>> Yep, that's what is being used here in the office although not for >>>>>> hobby. I believe you can legally use the Eagle free version if you do >>>>>> not design for profit. That would reduce your required budget for CAD to >>>>>> zero :-) >>>>>>> ... Years ago I >>>>>>> bought the home version of Electronics Workbench 5 with the board router, is >>>>>>> that worth learning? >>>>>>> >>>>> Hmm. 0 vs 0. >>>> EWB is free now? Last time one of my engineers wanted a copy we paid a >>>> few hundred but that was more than ten years ago. Way back when I used >>>> ECA224 and IIRC that flowed into EWB but I have to say I wasn't too >>>> impressed with EWB in the late 90's. >>>> >>> Unless i misread, i thought he said has an old version. >>>>> But not so much the learning curve. >>>>> Besides i detest doing anything twice without serious specific need/requirement. >>>>> >>>> Yep, same here, if something works for ya don't change it. >>> And after learning at least 4 different schematic capture / general CAD systems, i am >>> pretty much quickly productive in just about any such tool. >>>> [...] >> >> Same here. However, you will have to re-do most of the libraries every >> time you switch and that can cost weeks of boring grunt work. It doesn't >> matter how fast you are able to adapt, that work will have to be done no >> matter what. > > Perhaps. I think that everything not totally standard in most of my tools > is obsolete or proprietary. Not at all here. Then again I do a lot of switch mode converter design and there's lots of specialty chips and inductors. Same for the RF stuff I do. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: John Larkin on 9 Jan 2010 13:44 On Sat, 09 Jan 2010 00:29:57 -0800, rex <nul(a)msn.invalid> wrote: >On Sun, 03 Jan 2010 10:08:15 -0800, John Larkin ><jjlarkin(a)highNOTlandTHIStechnologyPART.com> wrote: > >>On Fri, 01 Jan 2010 19:19:42 -0600, krw <krw(a)att.bizzzzzzzzzzz> wrote: >> >>>On Fri, 01 Jan 2010 17:40:54 -0500, ehsjr <ehsjr(a)nospamverizon.net> >>>wrote: >>> >>>>John Larkin wrote: >>>>> On Thu, 31 Dec 2009 11:49:37 -0800, Joerg <invalid(a)invalid.invalid> >>>>> wrote: >>>>> >>>>> >>>>>>John Larkin wrote: >>>>>> >>>>>>>On Wed, 30 Dec 2009 20:02:02 -0800, D from BC >>>>>>><myrealaddress(a)comic.com> wrote: >>>>>>> >>>>>>> >>>>>>>>On Wed, 30 Dec 2009 20:01:39 -0600, "RogerN" <regor(a)midwest.net> >>>>>>>>wrote: >>>>>>>> >>>>>>>> >>>>>>>>>When I was in school components fit on solderless breadboards and we made >>>>>>>>>circuits using breadboards, power supplies, meters and oscilloscopes. Many >>>>>>>>>of today's components don't appear to be breadboard friendly, so how is it >>>>>>>>>done today? >>>>>>>>> >>>>>>>>>Is circuit design software and simulation good enough to go straight to a PC >>>>>>>>>board? Or do you use surface mount to breadboard adapters? Do you still >>>>>>>>>use a soldering Iron to solder or paste solder and an oven? >>>>>>>>> >>>>>>>>>I'm wanting to tinker with some circuits but some chips I'm interested in >>>>>>>>>only comes in MSOP or other packages that look intimidating to attempt to >>>>>>>>>solder. >>>>>>>>> >>>>>>>>>Thanks! >>>>>>>>> >>>>>>>>>RogerN >>>>>>>>> >>>>>>>> >>>>>>>>My motto: >>>>>>>>If it works on a breadboard, it's not worth producing. >>>>>>>> >>>>>>>>On my current project, I have to feed the simulator pcb parasitics and >>>>>>>>component parasistics to get accurate simulations. >>>>>>>>I've had to bench test to get some parasitics. Once parasitics are >>>>>>>>included, scope results and simulation results get close. >>>>>>>> >>>>>>>>If all looks good on sim, I make a pcb, etch it and bench test it. >>>>>>> >>>>>>>One problem is that device models often aren't available for fast >>>>>>>parts, or all you get are S-params when you need large-signal >>>>>>>time-domain stuff. So sometimes you can learn a lot by hacking some >>>>>>>FR4 and testing parts. >>>>>>> >>>>>>>I never breadboard entire products, or even complex circuits... just >>>>>>>enough to characterize parts or simple subcircuits. >>>>>>> >>>>>>>This is an EL07 driving a PHEMT... >>>>>>> >>>>>>>ftp://jjlarkin.lmi.net/BB_fast.JPG >>>>>>> >>>>>>>which made decent 5-volt, 1 GHz square waves. >>>>>>> >>>>>> >>>>>>How do you get those nice clean cuts into the copper? >>>>> >>>>> >>>>> Just x-acto. The magic trick is to then rub it hard with a Scotchbrite >>>>> pad. That removes the burrs. >>>>> >>>>> John >>>>> >>>> >>>>You've got a steadier hand than I'll ever have. >>>>I have to do it with a Dremel mounted in a drill press >>>>adapter, and slide the board against guides clamped to >>>>the bed. Even then ... :-( >>> >>>Sounds like you need a small milling machine. >> >>We had one of those PCB mills, on indefinite loan from a customer who >>wasn't using it. It was such a hassle that we wound up not using it >>too. >> >>I can do the modest stuff with a knife and some kapton tape. After >>that, it's easiest to just lay out a board and have a pcb house make a >>few. >> >>Teflon board material is a lot easier to x-acto than FR4. You can get >>it on ebay. >> >>John >> > >I like your hand work, John. It's a lot like things I have done. > >Here's a link to a picture of a test board I made a while ago... >http://www.xertech.net/pub/multiplier1.jpg > >It's a diode doubler for 5 MHz to 10 MHz on FR4, based on the two diode >doubler here: >http://www.wenzel.com/pdffiles1/pdfs/diodedbl.pdf >The lines are about 50 ohm impedance on this board. > >I did it so I could try a few different kinds of transformers like the >ferrite binocular one I wound in this picture. > >To cut the copper I use a round diamond dental bur. A few years ago I >bought 30 or 40 of a couple different types from a seller on ebay. >Something like current auction 260491962839. I think the ones I use most >were 1.1 mm dia round ball ends. I draw the lines I want to cut with a >fine sharpie and then cut it by hand with a Dremel. I find this faster, >easier and safer than a blade. Not too difficult to cut narrow lines, >especially if you do it under some magnification. > >If I need to remove a wider piece of copper, I cut the edge of the >pattern, then use a hot iron to unstick and peel the copper. > >You need a very small collet in the dremel chuck. I think the bur shafts >are about 1.6 mm dia. > >Here's another one I did this way... >http://www.xertech.net/pub/osc_reg.jpg > >I found a nice MTI 5 MHz OCXO on ebay. It was mounted on a small circuit >board that just fed it DC. The oscillator wanted only about 10 V and I >wanted to be able to run it from a 12 V battery, so I cleaned down to >copper on the back side of the board and cut some (planned) square pads >to add this regulator. > > Nice ones. I like this kind of breadboarding, and it works with surface-mount parts well into the GHz zone. Coplanar waveguide works great here. I also like edge-launch SMA or SMB connectors to feed in and out, or just a hardline pigtail with an SMA on the other end. Regular square-flange SMAs can be butt-soldered to both sides of a CPW board and make great edge-launchers... better in fact than "official" edge-launch connectors. I'll have to try some dental burrs. One could probably use a steel ruler as a cutting guide. I would follow up with my trademark Scotchbrite rub. Favorite diode: Skyworks SMS7621-079, 0.22 pF. Skyworks has a great sample kit full of various schottky, varactor, and limiter diodes. John
From: Jim Thompson on 9 Jan 2010 18:29 On Sat, 09 Jan 2010 13:20:32 -0800, Joerg <invalid(a)invalid.invalid> wrote: [snip] > >Federal law trumps state law, and most certainly county regs. So, there. > [snip] ONLY if not Constitutionally forbidden from infringing State's rights. ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
From: Michael A. Terrell on 9 Jan 2010 18:58 Joerg wrote: > > Michael A. Terrell wrote: > > Joerg wrote: > >> Haven't followed it lately but isn't there some sort of constitutional > >> right to access broadcast channels within reasonable means? I can't > >> speak to that off the top of my hat but I can tell you this: Local > >> authorities are often very mistaken as to what (little) rights they > >> really have to twist your arms using they local rules. A community board > >> here had to learn that the hard way and I was one of the reasons why > >> they did. > > > > > > http://www.tvtechnology.com/article/92802 > > > > Ok, but that doesn't say that they are thinking about curbing the right > to your own antenna by some local authority. Freedom of information has > a rather high place in our country and that's a good thing. What good is the right to erect any antenna, if they give the spectrum to someone else? Those special interest groups are out to take everything they think they can possibly use. Wi-Fi on Channel 2? Give me a break! If they get their way there will be no 'Free TV'. You will have to use cable or a sat service to get anything at all. Where is 'Freedom of information' if you have to pay for it every month? What is there to stop continuous rate increases if local TV is removed from the equation? HTH will you get information about local events or emergencies when a storm blocks reception of the Ku band? BTW, it looks like WOGX moved their studios to Gainesville recently. I will be near the old studio site in a few days and will see if it's still in use. -- Greed is the root of all eBay.
From: Michael A. Terrell on 9 Jan 2010 19:02
John Larkin wrote: > > Nice ones. I like this kind of breadboarding, and it works with > surface-mount parts well into the GHz zone. Coplanar waveguide works > great here. > > I also like edge-launch SMA or SMB connectors to feed in and out, or > just a hardline pigtail with an SMA on the other end. Regular > square-flange SMAs can be butt-soldered to both sides of a CPW board > and make great edge-launchers... better in fact than "official" > edge-launch connectors. > > I'll have to try some dental burrs. One could probably use a steel > ruler as a cutting guide. I would follow up with my trademark > Scotchbrite rub. You might like these, too: <http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=36252> > Favorite diode: Skyworks SMS7621-079, 0.22 pF. Skyworks has a great > sample kit full of various schottky, varactor, and limiter diodes. > > John -- Greed is the root of all eBay. |