What causes radio interference?

[Dick in Wisconsin]

Putting florescent lights in the new 1000sf race shop.

What is the typical source of interference for my portable Craftsman radio that can be plugged into 120volt or (more likely) a CM C-3 19.2 Ni-Cad or Li-Ion battery?

Is it the ballast? Or the fluorescent light tube?

Are there any ballasts I should stay away from? or any fluorescent light tubes I should stay away from?

 

[dogdog]

http://www.garagejournal.com/forum/showthread.php?t=148407


http://www.gelighting.com/LightingW...ectronic-Ballasts-Whitepaper_tcm201-78523.pdf

 

[Dick in Wisconsin]

http://www.garagejournal.com/forum/showthread.php?t=148407


http://www.gelighting.com/LightingW...ectronic-Ballasts-Whitepaper_tcm201-78523.pdf

Thanks! That should answer the problems.

Looks like the key is "residential" ballasts and good grounding!!!!

From the GE link:

"Grounding Proper grounding is the most important aspect to minimize EMI. A good ground path will shunt high frequency noise to earth, and a proper ballast ground is critical to meet the FCC requirements. A poorly grounded fixture will act like an antenna and radiate the noise externally. Most GE ballasts are grounded through the ballast metal case. The mounting fasteners should make a good electrical connection between the ballast case and the metal of the lighting fixture. Use a star washer and scrape the paint from the ballast mounting tab to ensure a good connection."

Use a star washer . . . is this why I see star washers on so many electrical components?

 

[kd3pc]

ballasts hands down, while the "star" washer MAY help, it is all but a band-aid. As we consumers demand cheaper and cheaper prices, the manufacturers respond.

Even the "residential" ballasts that the big box stores sell, fixtures including them - are garbage noise wise....

IF these are new ballasts, you MAY get some replacements from the maker. I bought 8 new 4' fixtures last year, when finishing my garage, and they were midline Metalux, part of Cooper Group. They were "marked" residential, but when cooper looked at the fine print on these - they were NOT residential ballasts.

Kindly they replaced all of them, after an initial test of one, to make sure. It did cost me a few weeks of back and forth and some connectors (to replace the ballasts)....but they were stellar in their support.

I have an RF quite garage, and can play ham radio there, listen to the stereo FM with nothing but the little wire dipole and other radio/wireless stuff.

best of luck.

 

[ctfjr]

ballasts hands down, while the "star" washer MAY help, it is all but a band-aid. As we consumers demand cheaper and cheaper prices, the manufacturers respond.

Even the "residential" ballasts that the big box stores sell, fixtures including them - are garbage noise wise....

I have an RF quite garage, and can play ham radio there, listen to the stereo FM with nothing but the little wire dipole and other radio/wireless stuff.

best of luck.

Right on the mark. With the pressure on to drive down costs of a myriad of consumer products including fluorescent and led lighting emi is, unfortunately, a unwanted byproduct.

You may have an rfi free garage but unless you are far from neighbors or have built an rfi cage in the walls & ceiling, you are as most of us are, at the mercy of what crappy device your neighbor installs.

 

[DC73]

". . . Use a star washer and scrape the paint from the ballast mounting tab to ensure a good connection."

Good advice from GE. I don't know that a star washer is absolutely necessary if the ballast mounting screws makes good contact with an unpainted area of the ballast.

I used these fixtures in my shop: http://www.homedepot.com/p/Lithonia...al-Electronic-Ballast-C-2-32-120-RE/205431587

No noise or radio interference. But, I found by removing a screw from one of the ballasts that the chance of a good ground wasn't very good out of the box. So, I scraped the paint from the ballast, made sure the screw head was clean and made good contact with the bare metal on the ballast and I had no issues at all after installation.

Also make sure the ground wire for the housing has a good connection to both the housing and the ground in the junction box.

DC

 

[Cougar]

We replaced metal halide fixtures with six tube florescent fixtures. Radio reception is now terrible.
Maybe you should consider the led fixtures. Sam's has some good ones. http://www.garagejournal.com/forum/showthread.php?t=318464&highlight=sams

 

[Bigbandguy]

Sometimes you can improve things by getting a wire outside and dragging in a stronger signal. You can run some doorbell size wire out around a window, string it along the eaves and wrap the radio end around the ferrite antenna in the radio. Not very easy to do but sometimes you will get a much stronger signal which will overcome the noise. CFLs are among the worst offenders for noise. Good luck!