In order to achieve a better efficiency / luminous flux LEDs, these are probably operated in pulsed mode.
Since these are probably connected hard (rectangular pulses) occur in this case, of course, lots of RF interference (odd harmonics [See Fourier analysis])
In future I would use only 12 or 24V spots, with external power supply.
Benefits would be:
- Noise suppression can be secondary ('quasi' almost at the source)
- Transformer may at any time be replaced with a higher quality
- Transformer can be designed for the actual load
For me it is like this:
Light, radio is in reinforced concrete in stereo with all transmitters
Light on, this is no longer a station is, if so, but then extremely noisy
The more spots, the stronger the interference ...
My countermeasures for tolerably bad mono reception:
Ferrite close to the base (2 times performed)
Looking for a new place for the radio
Antenna alignment 'optimized'
