Frequency of Halogen Lamps

If you are talking about incandescent tungsten-halogen lamps, there would be no significant RFI. Are you talking about some kind of discharge lamp through a halogen arc?

Bill

-- Fermez le Bush

| Can anyone please point me to a Web site or study available online that | discusses the actual radio frequencies that halogen lamps (particularly | 120 Volt spotlights) emit. This is not about RFI in general but | specifically what frequency range is the RFI! Also, do you know if the | same information is availablefor sodium street lamps as well.

Halogen lamps emit whatever frequency they are operated at. Usually they are operated at 50 or 60 Hz, often at a lower voltage like 12 volts so they can use a thicker filament that can burn hotter. These are just a special form of incandencent bulb designed to burn hotter and be a bit more efficient.

Sodium street lamps generally also operate at 50 or 60 Hz. But they do need a ballast to regulate the current flow, and new electronic ones can do this with variable pulse width timing at some high frequency. The exact frequency varies. Some work at the AC frequency much like a common dimmer. Some work at a much higher frequency. Some "chop" up the AC and others convert to DC then "chop" that (hopefully alternating if the bulb technology would be adversely affected by DC). To avoid annoying acoustics, those that operate above the power line frequency will generally operate above the hearing level, 20 kHz to 50 kHz.

I agree on halogen lamps. But for arc discharge lamps (including mercury, metal halide, HPS, LPS, flourecscent) the arc should radiate higher frequencies. The OP might try sci.engr.lighting.

-- bud--

somebody knows if a plasma globe can be lit from a fluorescent lamp ballast, or an electronic ballast of the type used in compact fluo. bulbs. I think frequency 20 kHz is OK. but I don't know about the voltage.

If you take one apart, you will find it has a TV EHT transformer inside, so I don't think you'll get anywhere with a fluorscent lamp ballast.

Thank you, I have researched more now to know it would have never worked, because those ballasts give only high freq not high voltage. So I should use flyback. But, I may avoid the flyback driver and the 12 volt transformer by supplying the 20 kHz from an electronic comp. fluo. lamp ballast and reducing the voltage in some way I don't know. Would this work?

--------------------------------- Juan

just to add some info: i am trying to make a plasma lamp, and here (Argentina) the wall power is 220v/50Hz.

Please just go and buy a plasma lamp. It will work, and it will be a lot safer than one you knock together yourself.