RFI protection concepts
Posted: Tue May 27, 2014 7:21 am
I would like to discus RFI protection concepts.
I am using the concept below. XLR pin 1 to ground, and ferrite bead / ceramic cap filters on signal leads.
Example from a recent design:
However, on the outputs my configuration is different than several examples from very well respected people, see below.
From the RHAT1646 datasheet:
El Cheapo from Ricardo:
It seems this is a different idea, of just providing a low impedance to ground, and a high impedance into the circuit, thus steering HF energy to ground instead of into the circuit.
My idea is just HF filtering the output leads, just as any other “antenna “ connecting to my box.
Any ideas & opinions over which concept works better and why?
I am a film sound recordist. After education in Electronics I have been designing part of my gear (Hi-Fi and Pro audio) for about 30 years.
The biggest RFI problems in film sound recording are nearby Cellular Phones (cast & crew, 900MHz-2,4GHz) and our own Wireless Microphones (usually around 600-800MHz)
Regards, Gertjan Miedema.
I am using the concept below. XLR pin 1 to ground, and ferrite bead / ceramic cap filters on signal leads.
Example from a recent design:
However, on the outputs my configuration is different than several examples from very well respected people, see below.
From the RHAT1646 datasheet:
El Cheapo from Ricardo:
It seems this is a different idea, of just providing a low impedance to ground, and a high impedance into the circuit, thus steering HF energy to ground instead of into the circuit.
My idea is just HF filtering the output leads, just as any other “antenna “ connecting to my box.
Any ideas & opinions over which concept works better and why?
I am a film sound recordist. After education in Electronics I have been designing part of my gear (Hi-Fi and Pro audio) for about 30 years.
The biggest RFI problems in film sound recording are nearby Cellular Phones (cast & crew, 900MHz-2,4GHz) and our own Wireless Microphones (usually around 600-800MHz)
Regards, Gertjan Miedema.