RFI Causing issues with neighbors china cabinet

[K9ZMD]

Opening up & modifying someone else's appliance is a risky idea from a liability standpoint. Those might be the nicest neighbors in the world, but any sort of accidental damage or injury (fire, electrical shock, whatever) that can be even remotely attributed to the work (or alleged harm to the appliance) that you did, then you are going to be dealing with their lawyers. Guaranteed. Offer advice, but do nothing to fix the lamp.

[W4PG]

Opening up & modifying someone else's appliance is a risky idea from a liability standpoint. Those might be the nicest neighbors in the world, but any sort of accidental damage or injury (fire, electrical shock, whatever) that can be even remotely attributed to the work (or alleged harm to the appliance) that you did, then you are going to be dealing with their lawyers. Guaranteed. Offer advice, but do nothing to fix the lamp.

This is really true!

While we should be more than willing as good amateurs to help neighbors with RFI problems, you run the real risk of serious liability should something untoward happen. Modify the light and it catches fire, for instance. Not good!! Much will depend on your relationship with your neighbors, however.

Most of these devices are not "defective," they are just not made to reject RF interference. In fact, if you look on your landline phone, assuming it's wireless, you will see wording that says that the device is REQUIRED to accept interference!! It's important to educate folks on the fact it's NOT the ham transmitter's fault, but the fault of the manufacturers who refuse to add the simple components necessary to prevent the problem.

With that said, something as simple as an RF choke is unlikely to cause Armageddon! However once you go down the road of modifying a circuit with the addition of electrical components such as capacitors, etc, you accepted responsibility for any problems that may occur later on.

I always recommend educating folks on the failure of manufacturers to make their stuff resist RF, then educate them on the proper ways of fixing the problem and suggest they hire a qualified person to do the work.

.............Bob

[KC9UDX]

I wonder then, what would be the legal ramifications if you bought the cabinet "as is" from the neighbor, modified it to work they way they expect it to, and then sold it "as is" back to the neighbor.

This is a fundamental problem with our society. If you modify the lamp and it catches fire because of your modification, then by all means it's your fault it caught fire. But, if it catches fire because of a random problem not due to your modification, it's still your fault. This too shall pass.

[4L4AGU]

Technically, it is possible to decrease sensitivity of the circuitry without going inside the lamp, but it won't look nicely from outside. I did this trick once, when I having the similar problem with the lamp (ac conditioner start/stop caused it to toggle on/off). I took a small insulated wire, wound about 20 turns of it at the power cord near it's entrance to lamp, and connected other end of the wire to the "sensitive" part of the lamp. Problem solved.

[K0BG]

I didn't read every post, so I might have missed something here. A 20 meter Hamstick, up in the air, apparently without any ground plane under it. The coax is choked using an ugly balun which almost never works as well as a ferrite one. So, I suspect the coax is awash with common mode.

[WX7G]

And the coax shield is the real antenna. It works.

[MW1CFN]

And there was me thinking the actual cabinet had an RFI problem!

Why? Because one day, this rather spooky phenomenon occurred.

It lasted for a couple of days, on and off (no obvious modulation or period) and then never came back.

Weird!

Any suggestions? I reckon the hinges were picking up RF when they were critically positioned. Or something like that...

[K8MHZ]

And the coax shield is the real antenna. It works.

They work without a balun, too. They are great for portable use, but have issues for use as a permanent antenna.

As mentioned, the coax is probably radiating. A FS meter is a great tool to check that. The 'bad' part is that losing that much of a vertical radiator may negatively affect the performance of the antenna system. And by performance, I don't mean as indicated by an SWR meter. I mean signal strength as measured from another station.

[KC6RHE]

to be clear, this is a 20 meter hamstick dipole. defiantly feedline radiation is a factor here but the choke did clean up 90% of that and moving the feedline position helps too.

hamstickdipole.jpg

[W9DTC]

I setup my buddipole one day and tuned around... eventually I heard a station calling and tried to respond. I was in the kitchen and the sink started running. Well, the sink is touch activated (much like their light).

Anyhow, I later discovered significant common mode current on my coax. Having resolved that issue, I no longer have any problems.