New answers tagged emc
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You need an EMI choke as close to the socket as possible. The wires supplying power to the lamp are acting as transmitting antennas and radiating RFI. This also could include the house wiring in the walls.
At shortwave frequencies, the lamp itself is too small in relation to a wavelength to radiate very far, unless your shortwave receiving antenna is close ...
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My guess is STP cable or equiv. In a heavier guage will be EMI quiet with 12V on any earth grounded DC should not interfere with DX from a PC PSU.
answered yesterday
Tony Stewart Sunnyskyguy EE75
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1
View these LEDs as EMI emitters just like black-brick battery chargers are EMI emitters.
If the LED is fed unfiltered non-DC, with fast edges, then only the faraday cage will suffice.
And if the black-brick should be poorly shielded (to block outside views of internal 200volt/100nanosecond edges), then that would need the faraday cage.
Otherwise, input ...
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Is any of these options better from the point of view of signal
integrity/EMC?
Assuming your RGB signals are somewhere between 1.8V and 3.3V logic and given the fact there are single-ended signals, they will be prone to emission.
If this is indeed on your concern list, I would recommend a couple of options which I've used in my past experiences:
Use ...
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One possibility is that you placed MOSFETs too far from IC and you have parasitic inductivity. As the problem persist when adding gate resistance, it would mean that ringing is not an artifact of gate driver circuitry, rather a load problem.
Further you say, that when changing the motor with a different one, this problem vanishes. In my opinion, you have ...
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For CE (or the new RED now) is not compulsory to use a RF shield. Using a shield will help you with unwanted spurious emissions.
That is, if you are radiating at 2.4GHz by your antenna, from your PCB there will be unwanted emissions at different harmonics frequencies 4.8GHz, 6.2GHz... etc, these emissions are regulated and you if you emit more than what the ...
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I've been brought in to fix numerous failed-the-EMI-test PCBs. Failure was often in the 400MHz range.
Cure was
(1) to stitch the various regions of GND much more securely (if no plane used), and
(2) use 1Kohm resistors in long PCB traces, which dampen any resonances.
Regarding the long traces: suppose there is a resonance at 400MHz. Why not insert ...
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Just drive the lines as outputs. Don't leave them as floating inputs.
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Looks like 15 PuLSes for 300 ms is 50 Hz rep rate.
Each pulse is likely as follows;
Pulse front time 1.2 us ± 30%
Pulse time to half value 50 us ± 20%
Current Max. 2,500 A ± 10%
Pulse front time 8 us ± 20%
Pulse time to half value 20 us ± 20%
Polarity Positive/negative/alternating
answered Jan 31 at 23:51
Tony Stewart Sunnyskyguy EE75
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1
Does anyone know what the time symbol they are showing there is?
I haven't used that equipment. However one guess is that 15 pls on the menu is 15 pulses (at the set period etc.).
To help to confirm/deny that guess, I would use a small voltage setting, configure an appropriate oscilloscope probing setup for that voltage, and I would view what simulated ...
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