You’re probably familiar with squelch, but do you know what your RF gain knob even does? Casual CB radio users usually don’t how these two settings work.
Some truck drivers may not understand the difference between squelch vs RF gain and how they work, but these two functions, but these are actually very different settings that work together to enhance the performance of your CB. Today We’ll talk about the difference in detail and tell you how to use those knobs to your advantage.
Squelch Vs RF Gain- How does it Work?
RF gain controls the CB receiver’s sensitivity. Squelch is an adjustment that filters transmissions by their signal strength. Together, these two controls are used to optimize both the range and sound clarity of CB radio reception.
Let’s get Into Details
When you look at the technical explanation, it may seem like there’s no practical difference between squelch and RF gain, but there really is. The devil is in the details as they say. Understanding that difference can help you get better range and clearer sound from your CB radio.
You can think of RF gain as a way to set the range you want to receive transmissions from. The lowest RF gain setting only lets you hear other truckers who are very close. The highest setting will let you hear transmissions from the furthest distance that your CB is capable of. Many experts recommend leaving the RF gain at its highest notch. But there are some instances where you would want to make an adjustment.
Notice how I said that RF gain determines the range from which you’ll receive transmissions, not conversations, which is key to understand. Your CB radio cannot tell the difference between someone talking into their CB and other forms of radio transmissions in the frequency of the channel you’re on. There’s a lot of other stuff coming in (or signals coming in). There’s power substations, microwave towers and even the sun all “transmitting” on all 40 channels at once.
All of those radio waves coming in bombard your radio’s receiver. If there was no way to filter it out, you would never be able to understand a single word being transmitted by other truckers on their radios. Do you know how to filter all that noise out?
Squelch is the filter. A radio expert would point out that the squelch function doesn’t actually filter anything in a technical sense. There is a lot more to it, but we’re talking in practical terms here. For all everyday practical purposes, squelch filters out noise.
About RF Gain
Not all CB radios have a way to control RF gain. It doesn’t add to the manufacturing expense, but many truckers just don’t care about it. They don’t see a reason to have another knob to mess with. This is understandable. But having a way to control RF gain and knowing how to use it can enhance your CB experience.
There are several instances where you would want to have this kind of control on your CB.
Let’s say you’re following another trucker as part of a big haul. You want to be able to communicate, even if you’re not in the mood for conversation. So you have to have your CB on, and you have to be paying attention and monitoring it. Without any control over the RF gain, you’ll have to hear yammering from every ratchet-jaw for miles in every direction. If you have an RF gain knob, you could turn it all the way down. You’d be able to hear transmissions from the trucks nearest you, without having to listen to trucks way on up the highway.
On the other hand, you may want to hear from drivers up the road. In that case, you would simply turn your RF gain up. The longer of a reach you want, the more you would turn it up. It works just like an OTA television antenna. You’ve seen them advertised as having high gain. That’s a brag that they can pull in TV stations from far away.
All CB radios have a squelch adjustment. Without it, all you would hear is white noise, or static.
Squelch works by filtering out transmissions based on their signal strength. Does that sound like RF gain? Well, it’s kind of similar if you don’t really think about it too much. It can be confusing.
Remember all those pesky transmissions I mentioned above? Every channel on the CB band is crowded with this radio pollution. And all that pollution comes from every direction. More importantly, it comes from all distances, near and far. If all of those stray transmissions came from far off, there’d be no need for squelch at all. The RF gain would take care of it with no problems. But that noise comes from base towers dozens of miles away as well as possibly the ignition system of your own truck. Anything that uses or generates electricity has the potential to create interference that manifests as static noise.
Squelch filters noise
So how does squelch filter all this noise out? It works by blocking signals based on their intensity. Someone talking into their mike even dozens of miles away is sending a powerful signal. Their radio makes sure their transmission is nice and strong. But radio pollution isn’t intentionally amplified like a CB radio transmission. The interference is therefore weak.
When you turn the squelch all the way down, which is counterclockwise for radios with control knobs, you’ll immediately hear static noise. Everything is allowed through, regardless of the signal strength. The weak interference from power lines and bits of conversation from the furthest reaches allowed by your RF gain setting, all intentional and stray transmissions on your channel’s frequency come through your receiver and out your speaker. When you turn your squelch all the way up, you will hear total silence. Nothing is strong enough to get through.
You want to set your squelch to the point where you aren’t hearing any static, but you can hear transmissions from other truckers. This takes a bit of getting used to, but it is intuitive for the most part. You’ll notice that your squelch setting is never at the absolute lowest or highest.
Practical Knowledge: How To Use Your RF Gain And Squelch Together
I know what you’re thinking. “Finally, we’re getting down to the nitty gritty.” Yeah, but it is important to understand how each function works individually. Otherwise, the way they work together won’t make much sense.
Have you ever been talking to another trucker several miles down the road, when all of a sudden his transmission got choppy? I don’t mean full of static noise, but just in and out. This can happen quickly if you’re talking to someone who’s traveling in the opposite direction on the interstate. The reason the transmission got choppy is because the distance between the two of you got too big. If you have RF gain control, you could turn it up in this case.
If you are talking to someone close, but are getting a lot of chatter from other truckers who are a bit further away, you can shut out the other truckers by turning your RF gain down. This will only really work if you and the driver that you’re talking to are going in the same direction.
Squelch is pretty simple to master. When that irritating white noise starts to break in on your conversation, turn your squelch up until it stops. But be careful. If you turn your squelch up too high, you’ll actually start filtering out CB transmissions. Like I said, your CB can’t tell the difference between intentional transmissions and radio pollution. If it could, there’s be no need for squelch or RF gain knobs.
So that’s how you use each control individually. Adjusting them in tandem will help you get the most out of your CB radio.
Let’s start from the moment you turn your CB on. Where should your settings be? Turn your RF gain all the way up. That way you’ll have the greatest reception range. Now turn your squelch all the way down. Yikes, just listen to that ugly static. Ease your squelch on up until the static disappears. There you go. That’s your optimal settings, at least for now.
As you get truckin’ down the road, conditions will change (atmospheric, terrain). The sources, relative distances and intensity of radio pollution will change every few yards. You are constantly moving through a sea of radio waves. That means that you’ll have to make occasional adjustments to your squelch. Inch it up when you get breakthrough static. Turn it down some if distant transmissions that you want to hear are being hampered.
Just leave your RF gain turned all the way up, for the most part. Ease it down if the channel starts to get too crowded. Of course, this can be a pain if the trucker you’re wanting to talk to is far away. Turning the RF gain down will cut him or her out. Turn it as far down as you can without losing your conversation.
The Wrap Up
Squelch vs RF gain isn’t a fight, It’s a balance. And it isn’t difficult to get that balance just right.
It seems a bit long winded, but having a good understanding how RF Gain vs Squelch will help you maximize the performance of some of the best CB radios that are out on the market. If you’re a casual CB radio user keep this handy article in mind whether you use a base station or you’re out on the road. Go ahead and experiment a little. Set your RF gain to its max and see what kind of range you get by asking other truckers what yard stick they’re at. Then see how far your lowest RF gain will get you.
If you want some fun to pass the time, ask other drivers if they know the difference between RF gain and squelch.