Outfitting a Lab

Basic furniture for an electronics lab are tables or workbenches, storage using shelving and drawers, stools, bookcase(s) and large white board. I picked up ESD safe tables and chairs from a company bankrupt sale.

Local hardware stores sell large tool chests on wheels which are good for hand tools. They also sell tall storage racks on wheels and clear plastic containers. I keep boards and parts for a project in one plastic container. Multidrawer storage container are good for loose parts, hardware, through hole parts, connectors. Engineering kits for passive surface mount components are handy.

The lab has various stations depending on the work. I have a computer desk, test bench, soldering rework bench, and a radio bench.

SMT Soldering Station

The most essential piece for working with SMT (surface mount technology) is the soldering station itself. I highly recommend the Metcal (now OKI) soldering pencil. These use 10MHz RF energy instead of a heating element. All of the heat is focus on the tip and the handle doesn’t heat up. Warm up time is a few seconds and the pencil is light and easy to maneuver.  Heat is controlled by interchangeable tips. I use broad high temperature tips for dealing with soldering power devices to ground planes and the tiny low temperature tips for soldering 0402 passive devices.

Soldering station accessories are sponges and a squeeze wash bottle with distilled water to keep the sponge wet, fresh solder wick of different widths, a solder sucker, solder cleaner and flux in a needle flux dispenser. Stainless steel tweezers are important – the one I use the most is the techni-tool SM109. I have a home made vacuum pick tool that I use for the larger parts.

A hot air soldering rework station is useful. You should be able to set the air flow and temperature, readouts are optional as you can tell more from the sound the thing makes. These have individual tips for different size components and mate to the 21mm nozzle. This size is common to the Hakko and various knockoffs of that hot air station.

A decent stereo inspection microscope with good illumination is necessary. These are a head with optics, lighting system and heavy base. I tried digital camera microscopes but the depth of field from the stereo vision is important when trying to rework.

Another very important piece of lighting and magnification is the Luxo magnifier lamp. Most work is done under this thing.

I use a Thermolyne hot plate for solder paste construction of boards and reflow. I’d recommend a laboratory style hot plate rather than a cooking one as the heat distribution is better with the lab style.  I also have 6″  chunk of stainless steel plate to slide the boards on or off the hot plate. An IR Thermometer can be used to accurately set the temperature.

Basic Test Station

The essentials are power supplies, digital multimeter and Oscilloscope.

Power supplies – A basic lab supply has adjustable voltage and adjustable current limit. I would suggest a single high current supply single voltage (0-20V 10A) and a dual low current supply (±0-40V 0.3A) I would check the supplies on an Oscilloscope to insure that when you turn them on or shut them off, that you don’t see voltage spikes.

Digital Multi Meter – These measure voltage, current and resistance. The 3 1/2 digit handheld DMM is a must to have. The desktop 6 1/2 digit like the Agilent 34401 will give you reliable precise readings.

Oscilloscope or “scopes” – These display multiple waveforms of voltage versus time. Originally they were analog and today most are digital sampled. One of the small lunchbox style 100MHz scopes is useful about 85% of the time. One can pick up a nice used analog scope for $50 to $100. The analog scope can sometimes see what you wont see with the digital scope.

The power supply and the multimeters need banana plug cables plus a test lead holder to organize them. Most DMMs come with test leads with fat tips. If you are trying to hit a pad that is 0.2mm wide, find a thin sharp tip test lead.

The above items get used daily. Other equipment for a lab that is less frequently used is the variable transformer, a frequency counter and function generator. I have a logic analyzer, I don’t use it much anymore. I have found the low cost USB-based protocol analyzer pods for USB, I2C, SPI, and CAN work better and easier to set up. The main computer has to be close to the test bench so the USB cables reach.



Leave a Reply

Your email address will not be published. Required fields are marked *

Enter correct number to post comment *