Static on NFHW.

[TNFrank]

So, how would someone get rid of all this static or is it just normal with an EFHW.

[Davichko5650]

4 minutes ago, TNFrank said:

So, how would someone get rid of all this static or is it just normal with an EFHW.

Not sure how high you have the AF gain set, but the S meter is showing only 1 S unit of noise, that's actually pretty good for the 10m band. The lower bands like 20 - 40, etc usually have more noise than that in an urban setting from my experience.

[TNFrank]

I set it at 5 to 15 depending on the static I hear. I stopped running it in the "off" position. Here it is all the way off.

[WRYZ926]

The noise floor will vary depending on your location and what is around you. A lot of things produce RF noise, from the electric lines to LED lights, to everyone's phone chargers. There is no way to get away from it short of going out to the middle of nowhere without any electrical lines or electrical devices.

Plus we have just had a bunch of solar flairs which will also cause RF noise.

This is part of how the HF bands are.

[Northcutt114]

Do you have a counterpoise wire running from the transformer? If not, the outer shield of the coax is going to function as the counterpoise and RF is going to travel down the outer shield of the cable and back into the radio. You'll need more than one ferrite bead to tame that. I'd recommend 7. Smoking Ape has a great video on this.

But, as others have said, you're radio is only showing an S1 level. That's fairly quiet. HF, I have found, is noisy. It's not like the full dead quiet of GMRS.

 

ETA: Just saw the second video...man. A noise floor of S6? That's super loud. I'd definitely try putting more beads on the coax from the antenna first and see what that does. Unless you're already running a separate  counterpoise.

 

 

[TNFrank]

I'm going to see about adding a counter poise. I'll have to figure out how long to make it and I'll use a fishing weight to keep it pulled down straight from the balun. The noise floor moves around depending on where I'm at on the Band. Some areas get really noisy then it drops out as you move away from that area then ramps back up as you approach another section of the Band. I'll make up a counter poise tomorrow and see how it works out.

[WRYZ926]

Here is the formula for figuring out the length of an EFHW counterpoise.  The counterpoise length should be 5% of a full wave length of the lowest band that the EFHW is tuned for. 

Examples:

10M x 0.05 = .5 meters/ 1.6 feet

20m x 0.05 = 1 meters/ 3.3 feet

40m x 0.05 = 2 meters/ 6.6 feet

The lengths don't have to be exact as long as they are close to the lengths above.

Or if you want to still use the coax as the counterpoise then place 5 - 7 clamp on ferrite beads at the lengths above. Measure from the unun when placing ferrite beads on the coax. So for a 10m EFHW you place the ferrite beads .5 meters/ 1.6 feet from the unun.

Five clamp on ferrite beads works well as a common mode choke for the higher HF bands. You do want to use seven ferrite beads for the lower HF bands.

Using a CMC - common mode choke is a must when using an EFHW antenna to keep RF out of your radio. And it doesn't matter if you are running 5 watts, 100 watts, or 500 watts. Using a CMC also works well for any type of HF antenna. You want to keep all HF from traveling down the coax and into the radio. I use a CMC with all of antennas. 

If you decide to use a separate counterpoise then place the CMC at the unun.

A CMC and counterpoise might not help with the noise floor depending on your location. Some locations are just RF noisy and there isn't much you can do about it.

[TNFrank]

I found an EM-25 choke for a decent price on Amazon and I'm going to try the bead trick on the EFHE coax. Thanks.

[TNFrank]

I tried the beads on the coax and it didn't help. Hopefully the HF Choke will do the trick. 

[WRYZ926]

If the ferrite beads didn't work and a CMC doesn't make a difference then the RF noise is something close to you and there won't be much you can do about it.

There are plenty of people that have a high noise floor at their home so they mostly work portable to get away from the RF noise sources.

You can get or make a hand held yagi or loop antenna for a VHF HT to try and chase down any outside sources of RF noise. I have had to do that to chase down noisy transformers. Once I identified the bad transformers I contacted the utility company and they fixed them fairly quickly. Now if it's a neighbor's LED lights, solar panels, etc then you will have to try and work with them to fix things.

[SteveShannon]

For me, raising my EFHW made a huge difference in noise as well as coverage. 

[TNFrank]

We have solar on the house, that might be it. Plus, living in a housing addition with tons of people doesn't help either. The RF interference seems to be on the high end of each band in the 380-390 areas. I hope the choke helps, if not I'll just have to live with it I guess.

[WRYZ926]

The solar panels are most likely the cause of your RF noise. It is not noticeable on VHF and UHF but it is definitely noticeable on HF.

Chasing down RF noise can drive you crazy. You could try to do something to make sure you solar system is RF quite but that could get expensive. I would try to talk to the manufacturer or installer of your system to see what they have to say.

[tweiss3]

You could try rotating your setup as much as you can, even 35 degrees might help.

That really isn't that much noise, now this is noise:

[TNFrank]

With the Dipole and the HF-009 the noise isn't nearly as bad as it is with the EFHW.

[WRYZ926]

8 minutes ago, TNFrank said:

With the Dipole and the HF-009 the noise isn't nearly as bad as it is with the EFHW.

Different types of antennas will pick up different levels of nearby RF noise.

[WRYZ926]

Now here is a high noise floor! That was on January 3 2026.  I had a high noise floor on every band but 20 was the worse.

[TNFrank]

At least I know the HF-009 works now. I was starting to have my doubts but it redeemed it's self the couple QSO's I made with it. Now if I can just get the noise off of my EFHW it'll be good.

[WRYZ926]

Try moving the EFHW around in different directions to see if that helps. You will have a null off the end of the antenna inline with the wire.

[Northcutt114]

20 hours ago, WRYZ926 said:

Using a CMC - common mode choke is a must when using an EFHW antenna to keep RF out of your radio. And it doesn't matter if you are running 5 watts, 100 watts, or 500 watts. Using a CMC also works well for any type of HF antenna. You want to keep all HF from traveling down the coax and into the radio. I use a CMC with all of antennas. 

If you decide to use a separate counterpoise then place the CMC at the unun.

For clarity...you run a CMC at the unun, then the coax to the radio with the ferrite beads on that, too?

[WRYZ926]

17 minutes ago, Northcutt114 said:

For clarity...you run a CMC at the unun, then the coax to the radio with the ferrite beads on that, too?

I run the CMC at the feed point on my vertical 1/4 wave and dipole antennas. No clamp on ferrite beads are needed when using a CMC.

When using an EFHW antenna with a separate counterpoise, then I place the CMC at the unun.

If I am not using a separate counterpoise, then I place the ferrite beads directly on the coax at the correct length from the unun. This allows the correct length of coax to be used as a counterpoise. See the measurements I posted above for the measurements to place ferrite beads on the coax when using an EFHW.

[Northcutt114]

18 minutes ago, WRYZ926 said:

I run the CMC at the feed point on my vertical 1/4 wave and dipole antennas. No clamp on ferrite beads are needed when using a CMC.

Interesting. I wonder if running a CMC on my vertical 1/4 wave would help with some of the tuning issues I am having. I currently do not choke it at all.

18 minutes ago, WRYZ926 said:

When using an EFHW antenna with a separate counterpoise, then I place the CMC at the unun.

If I am not using a separate counterpoise, then I place the ferrite beads directly on the coax at the correct length from the unun. This allows the correct length of coax to be used as a counterpoise. See the measurements I posted above for the measurements to place ferrite beads on the coax when using an EFHW.

This is all understood. I have 7 beads on my coax at roughly 6.6' from the unun. In that case you would not, also, run a CMC?

 

[WRYZ926]

8 minutes ago, Northcutt114 said:

Interesting. I wonder if running a CMC on my vertical 1/4 wave would help with some of the tuning issues I am having. I currently do not choke it at all.

No it would not help with tuning. a CMC only keeps RF from traveling down the coax and into the radio.

8 minutes ago, Northcutt114 said:

This is all understood. I have 7 beads on my coax at roughly 6.6' from the unun. In that case you would not, also, run a CMC?

No I would not. The 7 ferrite beads are the CMC in this instance.

[WSHL413]

5 hours ago, WRYZ926 said:

The solar panels are most likely the cause of your RF noise. It is not noticeable on VHF and UHF but it is definitely noticeable on HF.

Chasing down RF noise can drive you crazy. You could try to do something to make sure you solar system is RF quite but that could get expensive. I would try to talk to the manufacturer or installer of your system to see what they have to say.

Definitely a factor here in So Cal suburbia. My neighbor a few houses down the street is a ham. He experiences RFI as high as S9 on HF 10m and 20m. He turned off the mains to the house and ran the rig on battery power. RFI persisted, so it's an external source, either the power lines in the back yard, neighbor's solar installation and/or their air conditioners. He's doing more investigation to locate the cause.

I am fortunate - RFI around S1 during the day except in very hot weather when people run their air conditioners. RFI goes up to S5/S6 then.

[TNFrank]

Just another reason I hate living in the city.