Electronics

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The hackspace has acquired an amount of test equipment over the years. Here you'll find details of what we've got, and any available documentation.

Safety

Safety is key, don't take un-necessary risks. You are in an environment with inexperienced people around you. Be considereate of everyones safety. This is not intended as a full safety list. Listed here are the basics, you should read further into the subject on your own initiative.

  • If you see something thats dangerous, report it.
  • Don't leave sharp or hot objects lying around and keep them away from the edge of the bench
  • Turn off soldering irons when you leave the work area
  • Wear eye protection. Solder or even a soldering iron in the eye can cause blindness
  • Use the solder fume fan/extraction
  • Lead based solder and components are present at the workstation. Wash hands when you finish working

High voltages

Unless you are experienced in this area we do not advise working on high voltages.

If you have experienced in this area read the following:

  • Think twice before working on live mains or high voltage equipment. Do you really need to be doing that and are you experienced enough to know the pitfalls? Are the people around you safe to be near this area?
  • If you do work on high voltage equipment secure it via some means such that it cannot fall into your lap
  • Fit RCDs to mains plugs when high voltages are present in a project you are working on do not rely on the buildings RCD
  • Warn others around you if necessary of what you are working on
  • No lone working on open high voltage equipment
  • High voltage equipment should have a safety cover fitted when not being directly worked on
  • Do not leave anything with a hazardous voltage unattended - turn it off
  • Any home made projects must be safe for others to use and must conform to safety standards. Ask for advice if your not sure.
  • Personal projects with mains voltages inside should be safety fused
  • PAT testing should be performed on mains electrical equipment after opening. Part of this is a visual check, the other part is electrical. We do not have an electrical PAT tester at present.
  • Damaged mains cables can lead to fires

Test Equipment

Soldering

  • Hot air SMD rework station with soldering iron - Clean soldering iron tips and turn off after use to extend the tips life
  • Solder station - Solder and desoldering irons - Clean soldering iron tips and turn off after use to extend the tips life
  • Various other soldering irons - about 5 by the last count
  • Solder, leaded and lead-free (wash hands after use), magnifiers, cleaners etc.
  • UV exposure box (Needs glass repairing)

PCB board etching

Its great fun to etch your own PCBs. Unfortunately at present (2 April 2016) we do not encourage etching boards at the space due to various reasons including chemical disposal, though this may change over time. So please ask on the mailing list what the current status is. It is recognised that this would be a nice-to-do item. Update this section as soon as this changes!

Misc Tools

  • Bench lamp with magnifier
  • Magnifier headset
  • Tools
  • Wire of various sizes
  • Components free for members use within reason and some to buy which are owned by members

Tools we'd like

  • PAT tester (newish or in cal)
  • Higher specification digital storage oscilloscope, preferably portable with Serial decode options (I2C, SPI, UART) and deep memory
  • Spectrum analyzer, 50 ohm, Hopefully with generator and return loss bridge (portable would be nice too:-) )
  • RF 50 ohm cal kit
  • RF frequency generators
  • RF power meter
  • Function generators or Arbitrary waveform generator (ARB)
  • Linear dual 5A, 0-30V PSU
  • Bench multimeter (eg 5 1/2 digits or more)
  • Component sample books - SMD and TH, caps, res, inductors
  • Full size antistatic table mats
  • Power meter
  • Current probes
  • Metcal soldering irons (lead free types)
  • Small pick n place
  • Bus pirates (Yarrr Jim lad/lady)
  • PCB shear


External Resources

Schematic capture and layout packages

There are too many Electronics (EDA) design packages to name, but a few of the more popular ones are listed below.

  • Eagle CAD - Arguably the most popular package. Has a free version, but is limited in PCB size and layers. Available on Windows, Linux and Mac. A lot of PCB fabricators offer to take the raw eagle cad files to generate your PCBs instead of you having to generate gerbers. Eagle cadsoft is owned by Farnell/Element 14. You can link your parts to the Farnell website for live pricing. Though its easier to serrch onling and input parts from the website.
  • KiCAD - Open source unlimited layers. Much improved over recent years. Available on Windows, Linux and Mac.
  • Others are fritzing (open source cross platform), Design spark, circuitmaker,

Circuit Simulation

  • LTspice - Professional tool. Popular simulation software
  • Simmetrix - Professionsal tool. Free and paid for simulation software, node limited, but the limit is generous enough to use successfully
  • Various much simpler circuit simulation tools now exist

PCB Fabrication Companies

PCB fabrication is the act of making the PCB itself.

Huge numbers of PCB fabricators exist. Here are a few of the low cost companies. Most will accept Eagle PCB files directly instead of sending gerber files. Some fabricators provide design rule constraints files (.dru for eagle) used for your layout design rule checks (DRC). You should obtain these or input them before you start your layout as they will stop layout issues. Others fabricators provide gerber output CAM setup files for eagle. For KiCAD you will often have to set this up manually or via a PCB template. OSH park has some simple KiCAD design rule information on their website. One final thing is that many manufactures have a 'design guide' which is useful in understanding PCB technology and limitations.

  • Ragworm - UK. low cost PCB company
  • OSH Park - US. Good for very small PCBs. Other companies produce cheaper larger PCBs. Has an excellent PCB viewer which you can use to see how your files will look when made. Worth using just for this feature.
  • Elecrow - China. Cheap and cheerful PCBs in many colours - arguably the cheapest around
  • Seeed studio - China. Similar to elecrow
  • ITead studio - China. Similar to elecrow
  • Wurth Direct - EU. High quality PCBs, higher pricing than others. Overly complicated design rule constraints for each of their many different PCBs, but track/gap specifications are much improved over the other companies mentioned above.
  • Lady Ada PCB fabricator list
  • Various companies also make SMD stencils using for example mylar (cheap) or stainless steel (more professional long lasting)

PCB Assembly Companies

PCB assembly means putting the components onto the PCB.

We've no specific experience with low cost assembly companies to guide you with here. Though companies such as elecrow and other low cost PCB fabricators perform this service. Most PCB assembly companies have a stock of standard components. You will then supply the remainder of your components. Sometimes SMD reels are required and sometimes extra components are required due to losses when setting up the pick and place machines and ongoing losses due to dropped picks. If you are manufacturing small quantities with lowish component counts through hole is still an option, which many will hand assemble. In general you discuss these details with the assembly company before deciding whether you are right for each other.

Be aware that if your a hobbyist or are making a very low volume products, you need a manufacturer who fits you and your requirements. Large volume manufacturers will be less interested in you and your product. You may be put on hold messed around etc if your not important to them.

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