any electronics geeks here?

by John Doe 28 Replies latest jw friends

• 

  mustang

  I have Jesus telling me what to do and His load is light.

  I picture JW's coming to the door and telling them that their major detraction is that we know they are just there to ultimately coerce us into doing the door-door thing: it's stilted and unnatural and its not going to happen.

  Thinking about when WTS or local eLDERs talk about the "spirit being blocked", I get a little voice in me that says the whole WTS is "spirit blocked" (not "spirit directed") from the top down, constipated beyond relief.

  With these two thoughts, you are right.

  Anyway, when I am doing 'troncis and the engineering thing, I am fulfilled and I know where I belong.

  Mustang
• 

  Jim_TX

  I am an electronics technician... and probably know a little more than my 'title'.
  
  I do schematics, and pcb layouts - and design small circuits on the side. One of my circuits is up on the wall hooked into my solar panel and battery. It's been in operation for many months - and still going strong.
  
  I would recommend a few places where you can purchase parts - and other things...
  
  www.digikey.com - great for small to large parts orders...
  www.mouser.com - also great - they may carry parts that digikey doesn't
  www.jameco.com - good for small orders - they don't have too many parts these days...
  www.goldmine-elec.com/ - great for odd parts - some kits - solar cells and panels, etc.
  
  There are others out there, too.
  
  I have breadboarded circuits - and then do a layout for them. One place - if you need a PCB fabbed is...
  
  www.pcbfabexpress.com
  
  ...I've had several boards done by these folks - they are inexpensive, and good quality... well, if you keep them small and in low quantities. I can get about 5 pcbs that are 10in sq for less than $100.
  
  I'd say go for it - learn what you want. It's fun.
  
  Regards,
  
  Jim TX P.S. I use CAD software to do my schematics and PCB layouts. If you are interested in learning the software, you can usually use the demo versions of CAD software to do small designs - which helps the small fella who doesn't want to invest a lot of money. I use P-CAD 2006, but the ones you might look for are PADS or CadStar - if you're interested in this.
• 

  Nosferatu

  I worked at my job in electronics for ten years. Now I've moved on to a job that only requires VERY basic knowledge and soldering skills, but it pays more :)
  
  I've designed some of my own circuits, I've modified existing ones, but I really don't like the whole business of designing my own circuits, basically because it's incredibly time-consuming. I'm also not horribly fond of using breadboards, since I basically have to build the circuit two times: once on a breadboard and once on a piece of veroboard. Veroboard is basically a piece of circuit board with copper 'dots' on one side of it which lets you solder the components to it. I much more prefer using veroboard and socketing all my parts instead of using a breadboard. However, if you're just playing around with the components to see what they do, a breadboard is the way to go.
  
  As for buiding circuits, you can find schematics all over the internet. All you need to do is get yourself familiar with the symbols for the basic parts. Chips (or ICs) have pin numbers, and you need to familiarize yourself with how to count the pins, and where pin one is. Most other components are pretty straight forward on wiring them up.
  
  Do yourself a favor and study the basic symbols. Better yet, just use this list and then build yourself a circuit!
  
  Here's the list: http://www.jentronics.ns.ca/images/electronic_symbols1.gif
  
  You only really need to become familiar with resistors, capacitors, diodes, and transistors. Chips are usually labelled something like U1, U2, U3, etc, etc, on a schematic diagram. When you see a schematic with a chip, you may want to look up the data sheet for the finer specs on the parts. It will also give you an idea on how to count the pins:
  
  http://www.nxp.com/acrobat_download/datasheets/NE_SA_SE555_C_2.pdf
  
  Start off with something simple. 555 timer circuits are pretty simple. People make things like blinking light circuits out of them. Do a google search and you should be able to find tons of simple stuff that focuses on the 555 timer. The sites usually give you a list of the parts you'll need to build the circuit.
  
  I also wouldn't advise buying an expensive oscilloscope unless you can get one pretty cheap. I got mine at a garage sale for $10. Instead, you could get by with just a multimeter and a logic probe. If you decide to really dive into it, then get yourself a scope.
• 

  mustang

  Jim TX P.S. I use CAD software to do my schematics and PCB layouts. If you are interested in learning the software, you can usually use the demo versions of CAD software to do small designs - which helps the small fella who doesn't want to invest a lot of money. I use P-CAD 2006, but the ones you might look for are PADS or CadStar - if you're interested in this.

  There are shops that cater to "prototypers" and small runs, such as you mention that will give you a link to their software and throw that into the PCB fab price. Douglas was doing that: you could buy a "cage", connectors and proto boards; when debug was done, use their software and clean, neat bare boards would come back. Populate those to replace your wirewrapped kluges. I haven't used them in several years, but it was "one stop shopping".

  Kits are fastest way to get there from the beginners standpoint, if you can find them. The hunt is worth the effort.

  But when you get some time under your belt, the point arises when you have something that is so custom nobody else has it. The choice is some really horrible "cut and jumps" or make your own circuit boards.

  You don't HAVE to go PCB: you can do old fashioned point-point or do wirewrap. In fact wirewrap has been known to go to Production. I still wirewrap first, for debug.

  But when the quantities go up, WW gets real tedious. And with prices like we have been mentioning, the "breakpoint" may be less than 5 PCB's.

  It is possible to do 'multiples' on one PCB and route them out to separate them. But the bargain shops may not include routing or have a size limit that stops you. One place I worked bought a NC router to skip etching. So, "I won't route for you" didn't bother them

  Lots of possiblities

  Mustang
• 

  mustang

  Check EBay Item number: 350127461522

  This is the Heathkit 3300 Breadboard; the 3100 and 3200 are also useful, having different functions.

  I consider this one a tool and have used it for troubleshooting, research, design, debug, qualification/evaluation and production test/screening.

  Some times, I actually built a circuit that was giving trouble to modify and "play" with it.

  One consultant that I knew attributed his livelihood to one, for certain jobs.

  BTW, Heathkit still exists: they folded up into a specialty company that does the "educational services" thing. I haven't inquired, but their books and instructional courses are supposed to still be available. These 3xxx series items were part of that legacy.

  It could be a current item, but the EBay source is for sure.

  Mustang
• 

  Jim_TX

  "...or do wirewrap. In fact wirewrap has been known to go to Production. I still wirewrap first, for debug."
  
  Ummm... wirewrap? Is that still around? I just did a quick look-see on Digikey, and the only wirewrap IC sockets that I could find were 24-pin sockets. I do not think wirewrap is the way to go for a newbie. (Although, I have a gold-plated wirewrap board - if you're interested - I think it plugs into a VME backplane.)
  
  Besides... many of the newer ICs and other parts that are being released these days from companies are surface mount. Sooooo... if one ventures away from 'Kit Land', they will need to learn how to solder really well, and then get some sort of 'surfboard' printed circuit boards that allow one to do quick and dirty circuits.
  
  Plus, Radio Shack has a neat new system for prototypers - a whole series of round boards that can be modularized - and plugged together.
  
  Regards,
  
  Jim TX
• 

  Nosferatu

  - "you can do old fashioned point-point or do wirewrap."
  
  Before I quit my last job, I helped them throw out the old wirewrap machine. Well, actually I took some of it home: the paper tape reader. I'll NEVER come across such an antique piece of computer equipment again. The thing is huge, but it's a nice piece of computing history.
  
  For those who don't know what a paper tape reader is, it basically pre-dates the floppy disk. If you don't know what a floppy disk is, it predates the CD-ROM and flash drives.
  
  I'll have to agree that wirewrap is NOT the way to go, since it's ancient, outdated technology.
• 

  HappyDad

  Everyone here said it all!
  
  Electronics is a fascinating hobby. I started out building a lot of Heathkit items. Back in 1979 I built a complete "ham" radio station with accessories. The only Heathkit I had problems with was the 2 meter rig they had at the time. Can't remember which model it was!
  
  Talked all over the world with that radio. The HW-101 and all with a dipole antenna. I've gone through a few radios since then.
  
  This week I had to dismantle my station since I'm moving the first week of December.
  
  HappyDad (from amateur radio 3 land)
• 

  Jim_TX

  Yuppers - I've got the ET-3300 & ET-3200. You can find them sometimes at places like Goodwill (where I found my ET-3200 for $2.98), or other places that sell odds and ends.

  I've used both breadboards to prove circuits - and one was used to demo LED circuits to a client.

  The ET-3200 comes in handy when learning digital logic - like Flip-Flops. You don't need to provide a lot of external circuitry like switches, LEDs or a clock signal - it's built-in.

  In fact... these 'solderless breadboards' are the way to go if you're trying to prototype a new circuit. One of these, and a lot of the pre-cut color-coded jumper wires, and you'll get a circuit put together quickly. For surface mount devices, you'll still need the 'surfboards', but they'll plug into the solderless breadboards - and away you go.

  I used one of the surfboards to prototype my Hi-Power LED Constant-Current Driver circuit - prior to doing a PCB layout (the driver chip was a SOT 23-5).

  Regards,

  Jim TX