Have you ever looked at the underside of a pedal or the rear of a guitar amplifier and wondered about all those little symbols such as FCC, CE, CSA, TUV or UL? Why is it that we typically see those on products from the big players, but not on the boutique devices? What does ‘This equipment has been tested and found to comply with the FCC Part 15 limits for a class B digital device’ mean exactly? In this weeks’ episode of ‘What’s The Big Deal’, we ask ‘What’s the big deal with …….. Certification?’
The short explanation is that these are marks indicating that the products comply with various safety and performance standards around the world. The standards vary quite significantly between different nations, which is why we often see many different marks on one product. If the manufacturer is expecting so sell their product around the world, they will often indicate compliance with multiple standards with labels on the device. The European Community has a set of harmonized standards for different types of devices. The CE mark that you see on many products indicates the manufacturer is confirming that their product complies with these standards.
An interesting thing about the United States is that the majority of the standards bodies are independent groups. There are often few laws requiring compliance to these standards to be able to sell a product. So this largely answers our question about why we typically don’t see these marks on things such as boutique effects pedals: There is no law that says they have to comply. And complying is a significant undertaking. The standards are often complex and difficult to follow. Testing requires hugely expensive specialty facilities with vast arrays of costly equipment and expert test engineers.
If certification is not compulsory, it begs the question why do the manufacturers even bother? This usually comes down to a couple of things. In some countries, certain levels of compliance are compulsory, so a manufacturer will at least need to test to those if they expect to sell into those regions. Some standards bodies will recognize tests of other groups, so if you have to do compliance for one location, then some others may come almost for free. Some distributors or resellers may require compliance in order to resell a product, so that might have an influence. Lastly it just makes sense for larger manufacturers to develop and test to standards. It can help with design decisions and quality control, minimize support and legal issues, and most importantly, give the company and their customers reassurance that the product they have made is safe and functions reliably.
If you are manufacturing a digital device though, one set of rules in the US that you WILL have to comply with is the FCC Part 15. This recognizes that certain digital devices emit radio signals, even though this is not part of their intended operation. We refer to these devices as ‘unintentional radiators’. The radio frequencies that these devices emit have the potential to cause interference with intentional radiators, and its part of the FCC’s job makes sure that your whizz bang digital delay does not trash your neighbors WiFi or cause an international aviation incident over your back yard.
Recently I was involved in testing some Mission products for FCC compliance so I thought I would share some of the photos from the day.
Early in April 2015, myself and Missions CTO and designer of the Mission Gemini amplifier, took some Gemini units down to EMT Labs in Mountain View, CA.
Here’s a Gemini 1 inside the anechoic chamber. The amp is a 50 pound two feet high 1×12 combo. It looks tiny in the photo, which gives you some idea of the size of the chamber. The device under test sits on a metal turntable and is rotated through 360 degrees during the test so they can measure the emissions all the way around. The scary looking red thing is the receiving antenna. This is motorized and raised several meters in height, during the test, again to measure the emissions at different points.
Outside the chamber, here are the results being shown on a monitor. The goal is to stay below the red line, so far we are looking good as you can see.
Here’s one of the many racks full of test equipment. A decent spectrum analyzer alone can cost $20K. EMT has many millions of dollars worth of measurement gear.
This is a state of the art 360 degree anechoic chamber used for testing devices such as wireless routers and smart phones. The engineer told us it can take weeks or even months to complete testing on some smart phones.
Here’s some power emissions testing being done in a room completely lined with metal.
The door of the chamber is several inches thick with thousands of copper fingers around the frame. It’s lined with hundreds of little space shuttle like tiles for absorbing reflections.
We had a very informative and productive day at the lab. Thanks to everyone at EMT Labs for helping us out and completing our testing within a day. I’m happy to say we passed all our FCC emissions tests.
A version of this article was first published in Gearphoria. You can read the latest articles in Workbench Confidential at Gearphoria.com