Kenneth Wyatt – EMC design and training services

A consulting firm that specializes in EMC design, troubleshooting and training services to commercial and industrial manufacturers with global distribution in the consumer, computer, network & telecommunications, industrial and scientific industries.

Kenneth Wyatt – EMC design and training services

Kenneth Wyatt - EMC design and training services

DIY 6 GHz comb generator by Kenneth Wyatt

Most simple DIY comb generators seem to run out of steam about 1 GHz. I recently ran into David Bowman’s 2.4 GHz circuit and measured an upper usable range of about 6 GHz. While greatly attenuated above 3 GHz, this circuit should still be valuable for measuring semi-anechoic chambers in the GHz ranges.

Wyatt Technical Services, LLC
56 Aspen Dr. Woodland Park, CO 80863, USA

Facts of EMI and RFI from the Inside

Electromagnetic interference (or EMI, also called radio-frequency interference or RFI when in radio frequency) is disturbance that affects an electrical circuit due to either electromagnetic induction or electromagnetic radiation emitted from an external source.

Electromagnetic interference Wiki

Vertical polarized VHF- UHF biconical antenna

Vertical polarized VHF- UHF biconical antenna
170 – 1100 MHz with omni directional H-plane pattern

Who would know better about Radio Frequency Interference and ElectroMagnetic Interference more than the Hams or Amateur Radio Community.

If they have to communicate effectively using limited resources, they have to deal with EMI/RFI effectively, While they build their equipment or combat Noise from other Machines and Installations nearby.

This problem needs more practical involvement and experimentation to learn, compared to learning something like Digital Electronics.

Equipment and Electricals like SMPS, AC/DC Drives, Motors, Solenoids and CFL Lamps are to be built/reinforced for low EMI/RFI emission/radiation.

Sensitive Medical Equipment like ECG or even a Aircraft can be seriously affected by Noise.

Radio Frequency Interference (RFI)

EMI RFI Mains Filters

EMI RFI Filters are required in two situations, to prevent EMI from an Electronic Equipment Like A Dimmer, Thyristor Drive, SMPS or Switcher affecting other Modules in a System or Neighboring Equipment. The Second Situation is when a Sensitive Equipment Like a Medical Apparatus or Precision Measuring Instrument has to be Immune to any Noise from outside, as it can affect performance. EMI RFI Filter

Sometimes it is Accuracy that can get affected, but some electrical jolts can damage or desensitize fine sensors or positioning systems.

On the right you can see a Filter that i used to make long ago, This is connected in series with an Existing Mains Chord. It can also be Fixed in a Control Panel with a Clamp. One Y cap is Missing in this Piece. The Big one must be the X cap a higher Capacitance Value. The Y cap is Lower Value and withstands around 1kV, It is better if X cap is AC 440V.

Related Resources

Here is one type i encountered in many T&M Instruments along with TDK too. It was Schaffner – electromagnetic compatibility – International leader in electromagnetic compatibility (EMC) and power quality (PQ). EMC Filters, RFI Suppression Chokes, Feedthrough Components.

Schaffner – @SchaffnerEMC – EMC/EMI components, harmonic filters & magnetic components.