Radio interference from inverter

[Farmer]

I am supplying our home's AC power via a Chicago Electric 400/800 watt inverter.  For some reason the inverter generates so much radio interference that listening to AM or short wave radio broadcasts is impossible.

Our battery powered radio picks up strong interference whenever it is brought within 15 feet of our home electrical system and the closer the radio gets to the wires the more intense the interference.

What is the solution?

Is it possible that a better quality inverter would not cause so much RF interference?

Listening to FM won't solve our problem there is only one FM station in this area and I don't really care for what they choose to play.

[jacobs]

I believe all inverters create some RFI. You might consider installing an automobile radio and running coax cable from the radio to a distance outside your home where the RFI isn't a problem, then connect the end of the coax to an antenna. This probably won't eliminate all the hash, but it will make listening tolerable.

[jacobs]

Sorry, I missed your comment about shortwave. I use a Kenwood R5000 for shortwave, also with coax to an outside antenna.

[sk windpirate]

Most of the Cheaper inverters are a modified sine wave. They will give of a lot of interferance. You can get a true sine wave inverter, True RMS,BUT expensive. but they will give you clean ac power.

[12AX7]

Hello!

It's been some time since I've been active with ham radio or broadcast, and I've got no  experience with dc inverters.  With that said, I suggest looking at how things are grounded, and when you rule that out.. look at it again.

think "daisy" where all devices are grounded/connected at the same ground location.

Is the noise on  the power or being "picked up" via the antenna?

are your receivers 120vac?

An outside antenna up high.. real high  and some really good ground.

My Kenwood 440s doesn't care for the computer next to it.  

And they don't make radios like they use to..  

I have worked with AC motor drives and they through off some terrible RFI.

Some filter caps on the line might be worth trying, not sure what values would be needed.   .001 @600v ??

Might try a CQ to some of the active hams out there.

0cean November X-ray

Mark

[12AX7]

should have read more carefully the first time!

If your portable/battery radio is picking it up  it's a grounding issue at/with the inverter.

The house wiring (some/parts/all) acting like an antenna for the transmitter (inverter)

suppressors on the inverter, and a really good earth ground.

Also note that what makes a good earth ground for house hold and a good RF ground are not always the same.

Good luck!   Troubleshooting RFI problems can/will drive a man to drink!

[Farmer]

The inverter doesn't have any provision for attaching a ground.

Should I ground one of the screws on the case?  What about tying the negative lead from the battery bank to the ground?

The radio interference comes in both on 120 AC powered radios and battery.

I agree that my electrical wiring is acting as a transmitter antenna.

[Cloaked User]

Don't ground anything on the inverter till you have read the exhaustive (and exhausting?) thread about fifteen notches down on the Everything page, titled "Bonded/Floating Ground Question." Take a sandwich with you.

[Opera House]

Look for a device like a CORCOM filter on ebay or make one.  These consist of an small inductor in each power leg with a .001 to .01uF on the load side to ground.  Even something as simple as winding some lamp cord around a 2 foot length of iron pipe will do it, power runs parallel in the wire.  You still need the caps on the load side.

[wooferhound]

An inverters Output is mostly Square Waves

Square waves produce many Harmonic Frequencies at multiples of the Fundamental Frequency.

Coils of wire (chokes) are a Low pass filter removing High Frequencies

I'm not sure what value to use but Chokes will help a lot

[SteveCH]

What I did was to bypass the inverter for my Icom HF rig [well, the 2m rigs also] by running them DC. My house is set up for 12v DC and also the 110 v. inverter-supplied circuit. All the radios my wife and I have had [ham radios, that is] are set up to be plugged into 110 v. source but are really running off DC, I don't recall but think they are 13.5 v. or somewhere around there. If your house is set up for DC as well, you might think about running the radio rig that way; obviously, you'd need to figure out a transformer if your system is 24/48 v. or whatever. Just a thought, and we have no RF trouble. We use a Trace 12 v. inverter for other stuff, and, yes, we get RF on AM bands on some radios, though not all [talking about commercial AM radio, not ham stuff]. The newer radios we have don't show any trouble; the one that is about 20 yr. old cannot be used at all for AM....