Curing RFI from fluorescent Lights?

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K4TEC
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Curing RFI from fluorescent Lights?

Post by K4TEC »

My neighbor has just installed 4 banks of 4 fluorescent lights.
They are giving me 20 over 9 interference on the HF bands
He has given me permission to gain access to resolve this issue.
Anyone had any luck with filters.
I know the source of interference is the lights as when you turn them off the bands are nice and clear.
I would really appreciate any input.
Thank you, Martyn
k4zmi
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Post by k4zmi »

Ceramic capacitors on the input and output of each lamp to ground maybe. make sure the neighbor has properly grounded his power wire grounds at the lamps and his breaker box.
just figure out the values of uf needed to short out anything in the range of 1.8-29.9 mhz.
KA9FOX
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Post by KA9FOX »

Probably a long shot... but I have not had any problems with regular CFL lights, and there are some nice advantages of CFL over regular fluorescent tube lights. There are conversion kits that allow you to convert a tube fixture to CFL.

For example:

http://www.retro-bright.com/

- Scott
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K4TEC
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Post by K4TEC »

KA9FOX wrote:Probably a long shot... but I have not had any problems with regular CFL lights, and there are some nice advantages of CFL over regular fluorescent tube lights. There are conversion kits that allow you to convert a tube fixture to CFL.

For example:

http://www.retro-bright.com/

- Scott
Thanks Scott, I wish it was that simple, I cant change his lights, he is a dingbat who keeps extic plants and they are a kind of grow light system,, looks cool if your in to that kind of thing but no help for me as 20 over 9 on 40m is unreal,, I had him turn them off for a while and the bands were perfect until he turned them back on again,,,
So dont know what to do for now?
KA9FOX
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Post by KA9FOX »

Well, technically, he is at fault, as his lights are transmitting on licensed frequencies. Just like the power companies must do, he must correct the problem or stop the use of the lights.

If you are an ARRL member, you might ask them for assistance, as far as what things you or the owner could do to mitigate the interference.

But if they do not work, somehow you will have to kindly tell the person that he has a problem and must solve it.

If you get the FCC involved, they will eventually cooperate and send a letter to the home owner. Here's just one example:

http://www.arrl.org/files/file/Part%201 ... Device.pdf

- Scott
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K4TEC
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Post by K4TEC »

KA9FOX wrote:Well, technically, he is at fault, as his lights are transmitting on licensed frequencies. Just like the power companies must do, he must correct the problem or stop the use of the lights.

If you are an ARRL member, you might ask them for assistance, as far as what things you or the owner could do to mitigate the interference.

But if they do not work, somehow you will have to kindly tell the person that he has a problem and must solve it.

If you get the FCC involved, they will eventually cooperate and send a letter to the home owner. Here's just one example:

http://www.arrl.org/files/file/Part%201 ... Device.pdf

- Scott
Thanks Scott,, all be it that he is odd,, he is harmless and a nice guy and we get on well so I wish to keep it that way,, I recon it is the electronic ballasts,, I will maybe look out for a magnetic type?
I have put ferrite cores near his lamps,, thats didnt do a thing so will keep researching.
Best 73s
martyn
KA9FOX
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Post by KA9FOX »

I definitely understand the neighborly thing, don't get me wrong. But at some point, if things go bad, you may need to make the neighbor realize it is his problem, not yours, and that you willing to help... but ultimately it has to be resolved or he has to shut those lights off.

- Scott
k4zmi
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Post by k4zmi »

So, I recon nobody wants to try the simple solution of using filter ceramic capacitors to ground the generated rf at each end of each lamp. Roughly guessing, 0.01uf for each ceramic should make a world of difference. Just make sure they each have enough voltage rating to handle the lamp voltage.
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K4TEC
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Post by K4TEC »

k4zmi wrote:So, I recon nobody wants to try the simple solution of using filter ceramic capacitors to ground the generated rf at each end of each lamp. Roughly guessing, 0.01uf for each ceramic should make a world of difference. Just make sure they each have enough voltage rating to handle the lamp voltage.
Thank you so much for the close value of the ceramic caps
I have lots of them here, now to see if he is home tomorrow and can see if he minds me taking the boxes apart for a short while.

I have a Collins I have just parted out,, they have bunches of them to ground so I will use them.

Please dont think I have ignored your suggestion,, I had not worked out the value of the caps needed.

Best 73s and a Happy New year
Martyn
k4zmi
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Post by k4zmi »

That was the standard value for input caps to tube grid or to a transister. Or is it 0.01uuf? Anyhow, any value that will pass rf frequencies while blocking ac from shorting to ground.
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K4TEC
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Post by K4TEC »

k4zmi wrote:That was the standard value for input caps to tube grid or to a transister. Or is it 0.01uuf? Anyhow, any value that will pass rf frequencies while blocking ac from shorting to ground.
Thanks for that Scott,,, the ones I have here are 0.01uf
I am not going to have a chance to do this until next week as I am working on a web site hihi...
Best 73s
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