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 LED INTERFERENCE
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 Return to top of page · Post #: 16 · Written at 6:40:49 PM on 26 March 2019.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
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 Postcount: 7307

Not sure if it's in your budget but...

https://www.ebay.com.au/itm/223431200590

They are usually nicknamed 'Maggy lamps' and they take a 22 watt circular fluoro which are still available. Some have a pushbutton to start the globe as some models were never fitted with starters.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 17 · Written at 6:49:34 PM on 26 March 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
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 Postcount: 6689

I'm glad I mentioned mine, as it made me notice that I had accidentally left it on in the garage for nearly a week. Sad


 
 Return to top of page · Post #: 18 · Written at 7:32:16 PM on 26 March 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5258

I had two Jaycar LED flood lights both generated massive RFI. As they were new I returned them to point of sale. We do not have RFI specs & anyone that enforces them any more. As said my NBN box is about as quiet as Collins class sub & has to be turned off when one wants to calibrate a radio.

The other thing we never see is the environmental & energy cost of all of the electronic componentry in these things and the need for it. Bearing in mind that if an incandescent globe is made of glass & metal and 100% of it is able to be recycled; I would bet it requires a lot less uncomplicated machinery to make it.

With many mains Run LED type globes we could likely just use a primitive Rectifier, or them as the primitive rectifier & a heavy duty hot wire filament as a barretter.

Consider one of those head type Magnifiers. Some are over priced & the light in some is of dubious benefit. I use a 50W desk lamp & when that globe goes I might replace it with a LED. If I do, I will put a rectifier on its transformer & run the LED/s on clean DC


 
 Return to top of page · Post #: 19 · Written at 11:27:59 AM on 30 March 2019.
Labrat's avatar
 Location: Penrith, NSW
 Member since 7 April 2012
 Member #: 1128
 Postcount: 374

A question and a comment.

1. When we talk about L.E.D. Interference, are we really talking about their drivers/power supplies ?

2. I have sent in a picture of my Maggy Lamp, it has a different type of switch. Bed lamp style, and like a a watch face, glows in the dark.

Does anyone know how old these lamps are? The styling looks to me to be Art Deco. Just the lamp for working on period radios.


Wayne.

Maggy Lamp


 
 Return to top of page · Post #: 20 · Written at 4:46:20 PM on 30 March 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
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 Postcount: 6689

are we really talking about their drivers/power supplies

Yes. The LEDs themselves are no problem.


 
 Return to top of page · Post #: 21 · Written at 4:55:29 PM on 30 March 2019.
Johnny's avatar
 Location: Hobart, TAS
 Member since 31 July 2016
 Member #: 1959
 Postcount: 544

Diodes are often used to make noise generators, white noise or whatever, across the spectrum.
So maybe GTC , LED’s may be cause of some problems under certain conditions.
JJ


 
 Return to top of page · Post #: 22 · Written at 5:00:50 PM on 30 March 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6689

Yes, I'm aware of the inherent noise of diodes as components, but I believe we are taking about the strong EMR hash transmitted, typical of poorly designed el cheapo switch mode power supplies associated with LED lamps and LED lighting installations.


 
 Return to top of page · Post #: 23 · Written at 6:51:47 PM on 31 March 2019.
Brad's avatar
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 Location: Naremburn, NSW
 Member since 15 November 2005
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Photo uploaded to Post 19.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 24 · Written at 7:09:47 PM on 31 March 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6689

Does anyone know how old these lamps are? The styling looks to me to be Art Deco. Just the lamp for working on period radios.

Ah, the good old Maggylamp. Used to see those in many places. I'd date that one to 1940s/1950s. IIRC, my doctor had one on his desk. I recall him using such a lamp when digging out a problematic splinter in my hand when I was in primary school.

Does it have the original plug on it? That would be a good guide to its age.


 
 Return to top of page · Post #: 25 · Written at 8:03:33 AM on 2 April 2019.
Irext's avatar
 Location: Werribee South, VIC
 Member since 30 September 2016
 Member #: 1981
 Postcount: 470

Hang on to that original Maggy Lamp. They are built to last. The new ones tend to be rubbish unless you pay top dollar.

I've seen them before with that type of glow in the dark switch. Not sure how old though.


 
 Return to top of page · Post #: 26 · Written at 6:49:22 PM on 2 April 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5258

Yes! The LED driver is the issue, which is why I wonder about the costly electronics & the environmental footprint of making & assembling those parts. The ideal, other than individual resistors, is a certain number in series just as we did with valve heaters & then have a voltage / current limiter.

With enough in series it may not take much of a regulator LR8 will take 450V DC. "Silicon Ringing" is not unusual for some diode types & that's why they had capacitors across them.

As said my lamp has a nasty LV halogen, fed AC through a transformer. & I use the head type magnifier as that preserves depth of field & can be used with glasses.


 
 Return to top of page · Post #: 27 · Written at 10:57:30 AM on 3 April 2019.
Robbbert's avatar
 Location: Hill Top, NSW
 Member since 18 September 2015
 Member #: 1801
 Postcount: 2017

I don't have any LED lamps or Halogen lamps in my house. However I do have 2 devices which emit huge amounts of interference.

One is a TV Digital Tuner box that came from Big W. In fact it emits more interference when switched off via the remote control.

The other is the computer that is attached to my document scanner. If the scanner is turned on it makes more interference, that can be heard on the car radio up to 100m away.

All my other computers are fairly quiet RFI-wise.

Started running out of incandescent globes. Had to raid my storage locker for a few precious bulbs.


 
 Return to top of page · Post #: 28 · Written at 3:52:57 PM on 3 April 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6689

Started running out of incandescent globes.

I see them for sale on UK websites, but (a) would they survive the voyage, and (b) would customs confiscate them?


 
 Return to top of page · Post #: 29 · Written at 6:01:51 PM on 3 April 2019.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5258

The noisy computer here is an old job that I bought in 2000. It has had 3 power supplies but that really has not changed the radiation so its obviously coming off the motherboard. It is kept going to run a 360 column printer (circa1986) and some software including an AutoCAD.

It would appear from your experience & mine, that Jaycar has an issue & it is amazing that they allow it to still happen: Its not as if they have not been told?

I deliberately made my attenuator in a metal box so that nothing could get into it.


 
 Return to top of page · Post #: 30 · Written at 6:34:47 PM on 3 April 2019.
GTC's avatar
 GTC
 Location: Sydney, NSW
 Member since 28 January 2011
 Member #: 823
 Postcount: 6689

a 360 column printer

Never heard of such a thing. What make/model is that?


 
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