Excessive noise on SSB - USB & LSB

[SnowWalker]

I have two, 3 year old Galaxy DX959 radios that are giving me a lot of noise on the SSB frequencies. Is there anything that can correct this? My older CBs didn't have the noise on SSB that the new ones do. I know there is a filter problem with most modern CBs so, could this be a cheapy filter ptoblem in my Galaxies? There has been some fantastic skip this past week in much of our area; however, I have to crank the squelch up to near 60% to hear people. I was receiving some good signal from Kentucky a few days ago on LSB Ch. 6 but could not really understand much of the talk because of the noise.

 

[RFI-EMI-GUY]

Is there an RF gain control? Do you hear bleed over from adjacent channels/

 

[SnowWalker]

Yup. I have used every option I have on the radio but, the squelch still has to be sitting on near 60% to silence the noise. Anything lower on the squelch, it really roars away. There is very little channel bleed. I can set the clarifier to be where I need it, I moved the radio to the basement where there is no electronic interference and my SWR is sitting at 1.1; however, the noise persists. A ham operator down the hill from me thinks I have a filter problem as do most new or modern CB radios a SSB capability. There two three other CBers in my area who have SSB radios and they have much the same problem. The closest radio shop that will work on a CB is 220 miles from where I live so it is very frustrating.

 

[zz0468]

Is the noise there when you take off the antenna?

 

[RFI-EMI-GUY]

You mght try turning the RF gain control down to a point where the radio sounds acceptable, The system gain might be way too high. You can usually turn it down somewhat without affecting the sensitivity. Way up and the adjacent channel interference and IM distortion go up.

 

[SnowWalker]

Thanks tons guys. I am going to try all the suggestions. The old CB radio is still being used and appreciated.

 

[wtp]

how are you powering the radio ?

 

[MisterLongwire]

I have the squelch down where I hear static. This is CB you re referring to, right? Unless you are on a dead channel with another person thats fine.

 

[kruser]

Thanks tons guys. I am going to try all the suggestions. The old CB radio is still being used and appreciated.

When you engage the NB on the radio, does it change the noise at all?

As a test, you could find a battery to power the radio and then turn off ALL your circuit breakers. If the noise goes away, turn the breakers back on one at a time giving some time for devices to start back up, and listen for the noise to return. You can do the same by turning the breakers off one at a time while listening for the noise to change or go away. It will stop almost immediately when you kill the breakers if it is something in your home.

Moving the radio to the basement was not a bad idea but that also will not stop it from picking up noise like you are describing. That kind of common mode noise can come in on your power lines or cable tv cable and then radiate through your entire house regardless of where your radio is.
Another very common source of this noise are light dimmers and fan speed controls. Noisy light dimmers can wipe out the entire spectrum you can receive! The breaker off test will find that.

 

[SnowWalker]

how are you powering the radio ?

With a 115V AC to 12V converter that is plugged into a new, dedicated ciruit for the CB only.

 

[SnowWalker]

I have the squelch down where I hear static. This is CB you re referring to, right? Unless you are on a dead channel with another person thats fine.

It's a Galaxy DX 959 CB. It's hooked to a 22' Roof top, Ringo Ring, 5/8 wave antenna with a SWR sitting at 1.1 using an external meter.

 

[RFI-EMI-GUY]

Depending on band conditions, there can be a lot of on channel noise from the many thousands of radios used worldwide. If you tune with a general coverage receiver or spectrum analyser, the noise floor pops up every 5 KHz.

Sent from my SM-T350 using Tapatalk

 

[wtp]

to avoid any line or converter noise, could you try it on a battery ?

 

[SnowWalker]

to avoid any line or converter noise, could you try it on a battery ?

That was the first thing I tried. It didn't create any appreciable difference. I tried switching off all our fuse box breakers one by one; however, only one breaker lessened the static marginally. I am beginning to think that it may be the Galaxy radio its self or an outside source.

 

[prcguy]

How does the Galaxy radio work on AM? Same high noise level or is it normal with the squelch muting at a much lower setting? What is your S meter reading on AM vs SSB?

 

[SnowWalker]

How does the Galaxy radio work on AM? Same high noise level or is it normal with the squelch muting at a much lower setting? What is your S meter reading on AM vs SSB?

on AM the squelch is usually at about 40%. On SSB it's up around 60 - 65%.

The noise level on AM is well in acceptable range; at least to my ears.

SWR on AM stays pretty much on 1.1 & 1.5 on SSB. The radio is sending & receiving on a 22' Ringo style roof top antenna.

Being that I live so high in the mountains (1340 meters) (I forget how to convert that to feet now) I get exellent carry with my sending and receiving signal. It's just the bloody SSB that is driving me crazy.

 

[prcguy]

That's a little odd, AM receive bandwidth is about twice as wide as SSB and usually AM will need the squelch knob turned up a little more than SSB if you have lots of noise on the band. Have you disconnected the antenna as someone else asked previously? Do that and see if your S meter sits around zero both on AM and SSB and that the radio will squelch on both AM and SSB with the knob barely turned up. If that works ok then you probably have something in the neighborhood making lots of RF noise in the CB band and you would have to kill that at the source.

on AM the squelch is usually at about 40%. On SSB it's up around 60 - 65%.

SWR on AM stays pretty much on 1.1 & 1.5 on SSB. The radio is sending & receiving on a 22' Ringo style roof top antenna.

 

[bpittman]

Try using a temporary horizontal wire antenna. If you get less noise than the vertical you might be getting manmade interference. I've read where most manmade noise is vertically polarized.

 

[SnowWalker]

That's a little odd, AM receive bandwidth is about twice as wide as SSB and usually AM will need the squelch knob turned up a little more than SSB if you have lots of noise on the band. Have you disconnected the antenna as someone else asked previously? Do that and see if your S meter sits around zero both on AM and SSB and that the radio will squelch on both AM and SSB with the knob barely turned up. If that works ok then you probably have something in the neighborhood making lots of RF noise in the CB band and you would have to kill that at the source.[/QUOTE

 

[SnowWalker]

I have help headed my way around noon PST. The guy is a long time ham op. who works for a communications company. We will see what he comes up with.

In the mean time thanks a ton guys for all the offered help. I will keep you posted on the findings and out come.