LED Lights Interferes with DAB signal

Interesting thread. I’ve had the same trouble for the past couple of years, but it was today when I installed some new LED GU10 lights in the kitchen and the Archers cut out, that it became a big problem (for the Archers fan, the Mrs., which in turn made it a big problem for me!!).

A quick search and I found this thread and scanned it for any solutions. As there didn’t seem to be any quick fix, I got my portable, battery powered DAB radio and tried it in the kitchen where our other DAB radio is. This test lead me to record this video: LED Lights Interferes with DAB Signal - YouTube which shows how the aerial position and angle can help significantly in resolving the issue. The LEDs in the room I recorded the video in are some not-so-expensive 150 lumen ones from IKEA that I bought a couple of years ago.

Based upon this, my recommendation is to move your radio and try rotating the aerial 90 degrees in all axes.
 
Based upon this, my recommendation is to move your radio and try rotating the aerial 90 degrees in all axes.
OK as a bodge... But far, far better to eliminate the source of interference .. I.e. replace the badly designed LEDs.

NB for DAB the receiving aerial should be Vertical to maximise signal, as that is what is transmitted.

You wait until swmbo tidies the kitchen, moves the radio and loses the Archers again. :what:
 
Had some YouTube feedback that perhaps I should have switched the lights off to prove it was the lights and not just the aerial position so here's another video: .
 
It picks up a much stronger signal with the aerial vertical because the DAB transmission is vertically polarised.
When horizontal it picks up a much smaller signal, easily swamped by the RF noise from the LED lights (or theri switching power supplies).
This is as I would expect.
 
I have found two MR16 bulbs that do not cause my DAB radio to stop working. These were a Philips 5.5w non dimmable warm white which I got from John Lewis.
Philips 5.5W MR16 Energy Saving LED 12V Spotlight, Clear
http://www.johnlewis.com/philips-5-5w-mr16-energy-saving-led-12v-spotlight-clear/p231770874
I also tried a dimmable bulb, again from Philips a MASTER LEDspot
Philips 7W Master Dimmable MR16 LED – Warm White (36°) from these folks
http://www.energybulbs.co.uk/philips+7w+master+dimmable+mr16+led+-+warm+white+(36%B0)/4170295111
They are not cheap at £15 and £18.70 respectively but they do work and don’t interfere with the radio.
I've also had trouble with LEDhut MR16SMDN-3X1. I've tried three different lighting transformers plus a switchmode psu for an old external hard-drive, all with the same result; completely wiped out DAB.

Other than a shiny circular CE sticker there's absolutely no marking on these lamps. Who knows where they're made? Or whether they've really been tested for their CE conformity. :confused:

I would emphatically not use LEDHut bulbs. The ones I bought caused very high levels of radio interference when I plugged them into my existing circuits. (The same circuits those Philips LED MR16's are now in!). Their no quibble returns policy is a bit of joke as well as it took tens of emails and three phone calls to get them to give me my money back. They claimed that the bulbs were not faulty – it was my circuits.

I read somewhere that the CE test for these bulbs only requires no interference at 10 METRES from the bulb - which means anyone who wants the lights and the radio on in the same room at the same time is really pushing their luck.... (wish I could remember where I read it though.)
 
I originally posted my problem with DAB signals and LEDs about three years ago and gave up accepting a life of listening to the radio in the dark. I know have an unexpected solution!
In an attempt to boost reception on the DAB signal I went through a range of new aerials with and without boosters. They were all useless and I wasted my money but then a friend of mine who is an electronical engineer designed me my own aerial using some old coaxial cable and some cable ties mounted on a two meter length of wood (2"x0.5"). The cable had to be an exact length to correspond to wavelength with it coiled at one end and partially unsheathed at the other. Bingo! I suddenly have the best DAB signal which clearly swamps out the interference from the LED.
Everything has been working well and I have recently revamped my house internally with Celotex insulation on floors, walls and roof space so save on energy loss. Celotex is a kind of expanded foam double sided with a thick layer of aluminium foil. It's fantastic for heat insulation cutting my heating bills to one quarter however, the foil has created a box that kills dead ALL signals. The DAB signal I've solved by placing the aerial in the roof space and piping it in using coax cable. There is now no hope of ever using my MOBILE PHONE indoors!
 
It is not just Celotex which has aluminium foil, almost all similiar types of insulation also have it. As you say it is very effective in killing radio signals. Another problem is that with modern double/triple glazed windows the glass is coated with a very thin metalic layer, which also helps to kill radio signals.

Therefore, this problem is likely to get worse as more modern highly insulated houses are built. Therefore, the era of using small portable radios indoors is likely to come to an end. The only answer appears to be an external aerial or stream signals from the internet.
 
I've just got a Dab radio and could not figure out why at night reception was no good. According to Led Hut it's common knowledge that led lights knock out dab and they have closed my complaint. Yet there is no mention of this issue on thier website. Shame I bought ten of thier inadequate products which as useful as a chocolate fire guard. Avoid at all costs.
 
Bump from the past, as I was just going to post this.

Finally connected a wall switch up to my LED Downlighters (fed from a separate 12V driver that used to drive 12v halogen bulbs.

Thought I was going mad!

Turned on the lights and the radio went dead. turn the lights off and the radio starts up again.

These are the Nine new 3w lights that I fitted into my original halogen downlighters that used to burn 40w for each bulb:
https://www.amazon.co.uk/gp/product/B01HPO766O

Wonder if it's the lights or the two 12v transformer that runs them (one transformer runs 5 of them, the other runs the other 4 of them)
 
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Just started reading this old thread today, and I am astonished. .. Not that the notion that interference could be generated by LED lamps running from Switch mode supplies , but that vendors would openly sell them in the EU. There are a number of very clear eu directives including the CE marking which requires that the producer or the importer into the EU has such a mark and has therefore stated that it complies with appropriate EU directives. There are other directives regarding the generation and susceptibility of RFI , and it is clear that those lamps are not compliant. The complaint needs to be made to the trading standards office.
 
Just started reading this old thread today, and I am astonished. .. Not that the notion that interference could be generated by LED lamps running from Switch mode supplies , but that vendors would openly sell them in the EU. There are a number of very clear eu directives including the CE marking which requires that the producer or the importer into the EU has such a mark and has therefore stated that it complies with appropriate EU directives. There are other directives regarding the generation and susceptibility of RFI , and it is clear that those lamps are not compliant. The complaint needs to be made to the trading standards office.

Do you think killing the DAB signal stone dead would be due to the LED modules I linked to in my post above, or the 12V driver, that used (before I put in the LED's) drive 12v 40w halogen bulbs?
 
Do you think killing the DAB signal stone dead would be due to the LED modules I linked to in my post above, or the 12V driver, that used (before I put in the LED's) drive 12v 40w halogen bulbs?
Since the led modules run from 12v supply, and are non dimmable , I would suspect that they are not the problem and just consist of a number of parallel strips of 3 LEDs in series and a dropping resistor.or transistor. . Most likely the problem is the power supply driving them . If the unit driving them was simply a transformer a diode bridge and a capacitor ther would be no problem, but it is more likely a switch mode power supply creating 12 vdc from the mains.
If the power supply was intended for your 9 40w halogen lamps, it is much more powerful than your current needs. 400w compared to 27w. So a smaller PSU can be used.
 
I'll have a try with the leds unplugged.

The 12v power transformers are around 25 years old, and yes, two of them were originally fitted, by the kitchen fitter to power two runs (5 and 4) 9 in total 40w halogens.
The only reason I did not change them is, Why....
They gave out 12v, they were already there, and not really used a lot, so I'd just carry on with the same.

But yes, they must be way way over powerful to drive the tiny wattage of the leds as you say.
If I was to look for a replacement, is there something I need to look out for, re the interference aspect?
 
The best test would be to remove the LEDs and put in a halogen in each of the two circuits and see if that interferes. 1 halogen is about the same consumption as the string of 9 LEDs. If there is still interference, then it is those trafos. If not it is the leds.
It is slightly off point but circuits designed for halogen may be highly unsuited for LEDs. ... The halogen bulb is just the same fundementally as the old fashioned bulb. As it heats up, it's resistance increases, the current drops and it stabilises at a temperature and brighness and colour at which the power going in equals that going out as heat and light. Increase the voltage and it stablises at a slightly higher power , reduce the voltage and it gets a bit redder.
A led lamp is very different as the colour is independent of the current and more importantly as the lamp heats up, the current going in will increase because it's resistance actually drops ,heating it up and making it brighter , as more current flows in a vicious circle until it s melts. They therefore need a voltage and current stabilising circuits. This current limiting circuit may be already built into the led modules , particular if they were intended as halogen replacements. .
 

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