Here are some common questions asked regarding FCC ID testing for typical RF remote control transmitter, should you have any questions, please let us know.
Q1 – What is the difference between intentional and non-intentional radiation?
A1 – An intentional radiator, normally known as transmitter, radiates a controlled frequency. An non-intentional radiator radiates unwanted RF frequencies such as spurs and harmonics of the later, such as a DC motor when working, measures must be taken to control the radiation levels.
Q2 – Do I have to resubmit product for qualification if the product is modified even slightly after received an FCC ID number?
A2 – After receiving certification that test subject has been accepted by a regulatory agency, any modification normally means re-qualification. This situation depends on the level and type of modification, such as antenna changes to modulation to carrier changes. Be sure to consult your compliance testing labs to see if in-house re-qualifications can be made, and the necessary procedures.
Q3 – Why is sharing air frequencies so important in ISM band?
A3 – One of the benefits of the ISM band is that license is not required, however the use of ISM frequency must be done in organized and regulated manner. This not only reduces the chance of interference between signals, but also promotes safety. For example, if transmission is not regulated, one continuous transmitted high power remote control should cause signal jamming in specific areas.
Q4 – Is a radio receiver considered as intentional radiator and does it need to get FCC ID before marketing?
A4 – Even though RF receivers are considered non-intentional radiators, compliance testing still needs to be done. Most of today’s new generation receivers use super-heterodyne modules, thus has low emssion from antenna port, so meeting compliance is typically not a issue. While for older generation super-regenerative receivers, it has high levels re-radiation from antenna port, so it might be a issue to get compliance testing. Also receivers needs to go through other tests such as susceptibility and immunity test, and here at Solidremote, we only use superheterodyne receiver modules, which can pass FCC or CE R&TTE labs test without problem.
Q5 – What are typical RF lab tests that could be issues in qualifying a product?
A5 – Fundamental power levels, occupied bandwith, spurs, harmonic products of fundamental operating frequency, unintentional radiation while turning your product off and on, all the above parameters are described by a regulatory agency’s standards, even to extent of describing the setting and placement of the test equipment and orientation of the remote control transmitter device under test.
Q6 – What is periodic mode operation of remote control transmitter?
A6 – It’s mode of operation that has a prescribed number of burst periods and off period of transmission, typical appliances include garage door openers, automotive remote keyless entry etc.
Q7 – What is continuous mode operation of remote control transmitter?
A7 – It’s mode of continuous in operation that is beyond the allowed time period specified by Paragraph 231, Section A. To operate in this mode, limits in Paragraph 231, Section E may be applied.
Q8 – What is random mode operation of remote control transmitter?
A8 – Transmission of a signal that is not done in a pre-defined or pre-determined fashion. An example is when transmission is achieved with the use of push button, typical appliances include garage door openers, automotive remote keyless entry etc.
Q9 – What does DUT / EUT or UUT mean in FCC ID testing report?
A9 – Device under test – DUT, also known as equipment under test – EUT or unit under test – UUT, is a term commonly used to refer to a manufactured product undergoing testing in labs.
Q10 – What is the recommended step to submit product to compliance labs for testing?
A10 – The basic idea would be work together with your compliance lab at every stage, and conduct a pre-compliance measurement before officially submit the EUT to final testing, the pre-compliance measurement is first taken to point out any obvious over the limit violations such as excessive fundamental or harmonic power levels, or transmitting time beyond allowed limit, so we can make corrections if there is any, before setting product up for a full compliance test.
Q11 – Why or what is regulatory compliant testing such as FCC ID or CE R&TTE?
A11 – Any product on market that is considered an intentional or non-intentional short-range radiator that will share air transmission frequencies must go through compliant testing. The regulatory requirements will give guidelines so all devices in certain range will work together in a efficient manner. In the USA, FCC is responsible for regulating all RF devices, in specific, the CFR 47 Section 15.231 will be used to describe what requirements are to meet by RF remote control transmitters like garage door remotes, gate remotes and others, it’s advised always consult an experienced compliance testing house to recommend what section is applicable for your RF product corresponding to desired market place, and work with compliant testing house in every testing procedure.
Q12 – Can I use any frequency between 260Mhz and 470Mhz for remote control transmitter project in USA?
A12 – Even though above implies operation frequency span from 260Mhz to 470Mhz, the allowed FCC ID frequency range is from 40Mhz to above 470Mhz with restricted bands described in CFR47 Part 15, the restricted bands details can be found in Paragraph 205 in the above, restricted bands only allow a much lower radiation power level, thus is not practial for most RF devices usage, due to very limited value.
Q13 – What’s the expense of FCC ID compliance testing?
A13 – Usually the compliance lab test charge is around $2000 dollars, that not include early prepare of documents and fine tuning with factory, so total cost would be higher, always consult your local testing lab for a estimated cost.
Q14 – Which design do you recommend for FCC ID or CE R&TTE product?
A14 – Since technology is constantly improving, now we primarily use Silabs’ Si4010 chip or similar RF IC for new development project, the built-in adjust output power by programming feature will make pre-compliance testing progress much easier, and the final product is much more stable also, since it eliminates many surrounding components by integrating them into SoC chip.
Q15 – What does RBW mean in spectrum analyzer testing?
A15 – Resolution bandwidth or RBW determines the fast Fourier transform (FFT) bin size, or the smallest frequency that can be resolved, smaller RBW is able to show more precise radio wave.
Q16 – How is isotropic antenna differ from PCB loop antenna in testing?
A16 – The main difference here is antenna efficiency, a proper chosen isotropic antenna usually can emit full transmitting power from chip, while loop antenna’s efficiency is usually very low, typical efficiency in handheld transmitter is around 10% at 315Mhz, and 30% at 433Mhz, so the chip’s delivery power setting is very different when using different type of antenna.