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Circuit board techniques

Toner transfer, Press-and-Peel(tm), photoresist, Sharpie, nail polish.

Ferric Chloride vs. Ammonium Persulfate and other etching chemicals.

How to dispose of etchant.

Commercial PCB fabrication.

  • BatchPCB, by SparkFun -- Our hosts! $2.50 / square inch, must use your own software to generate Gerber files. Easy-to-use web ordering interface, but slow turnaround time -- 10-20 days. Boards come out very nice -- precut, double-sided with silk screen and solder mask on both sides
  • Olimex Bulgarian PCB manufacturer - $33 for a 6.3" by 3.9" board. I.E. cheaper than BatchPCB, but with a minimum board size requirement, silkscreen on one side only, and a more complicated ordering process.
  • PCB123 Offers their own free (proprietary) schematic and PCB layout software -- easy to use, but you are locked into using their service. Integration with ordering system simplifies the process of ordering boards. Cost (?)

Construction techniques

Dead bug style. Manhattan style. Veroboard. Perfboard and point-to-point. Solderless protoboard.

"solderless breadboard" is the fastest construction technique ... but it is very fragile. Also, the parasitic capacitance and sometimes intermittent connections can drive you crazy.

traditional perfboards with holes on a 0.1" grid (2.54 mm grid) come in many styles:

  • just holes in insulator
  • little donuts of copper around each hole; may or may not be plated-through (See this robot controller for an example)
  • Specific patterns of copper like stripboard / Veroboard™, or the common rails-and-short-strips pattern that's handy for DIP components
  • solid sheets of copper, usually with a little donut gap around each hole.

The best one to use depends on what kind of circuit you're putting together.

With these perfboards, there's 2 ways to connect wires so they don't fall off:

  • wire wrap, or
  • solder.

Front Panels

Its easy to make groovy front panels so your black boxes look the goods.

  • Use any graphics program to produce and print your art work.
    • Measure the box up, draw in the switches, label the LEDs etc.
    • Even print on user instructions.
  • If the front panel contains LEDs I pre punch the printout so that when it gets laminated it creates a window. No need for bezels :)
  • Laminate the printout.
  • Punch out the switch, screw, bnc, pot etc holes.
  • If there isnt many front panel "things" to hold the laminate to the box lid I use double sided sticky tape.

The beauty of this approach is that it also doubles as a drill template for the lid. Everything fits, everything looks square.

Soldering techniques

How to use a soldering iron. What is flux for?

Hot air soldering. Huh?

Hobby replacements for commercial reflow: skillet soldering, toaster-oven soldering, soldering using an oil lamp or candle.

How to fix mistakes: solder braid, solder sucker.

How to deal with fine pitch SMT devices.

How to deal with big, heatsucking components.

Other techniques

How to get started with a multimeter

How to use an oscilloscope: Tektronix's guide