How To Find Two-Way Radio Frequency

While you are in search of the correct frequency for your two-way radio you'll find several challenges. The core of these challenges actually lies in only two phenomena. The first one is related to the distance of your radio from the signal station and the second one is about to the obstacle.

 To prevent these challenges your two-way radio, need to be blessed with the perfect combination of two unique of frequency system. The first one is UHF (Ultra high frequency) which have a higher frequency of shorter wavelength.

The another is VHF (Very high frequency), having longer wavelength with comparatively low frequency. Actually, your two-way radio is blessed with the presence of all these two waves simultaneously.

But their range and combination of settings are different. Hence, to find the correct frequency, your only deed is to find the correct combination of these two wavelengths.

Basic function of a two-way radio wave

A two-way radio wave is actually a completely horizontally traveling wave system. So, the curvature of the earth creates the greatest obstacle for the transmission of this wave. The two points on the earth, where the distance can be counted as a straight line, will be the effective range for two-way radio transmission.

The range might be 4-6 miles. You can also calculate the range mathematically by using a simple formula. The range will be about 3.569 times in kilometersif you calculate the height of the radio in the metre.

So, you can make the range of your radio about 3 miles by placing it on 6 feet high from the ground. Thus, you can enhance the range up to 20-30 miles easily by placing your radio about 40 feet above the ground.

Characteristic behavior of the common two-way radio waves

UHF and VHF are the widely used radio waves all around the world. Both of these waves are used combinedly in a two-way radio system.

UHF (Ultra High Frequency)

It has high frequency but short wavelength. Because of high frequency, it can transmit greater energy. Its applied frequency in radio varies from 400 to 512 MHz usually. Its wavelength is near about only a several feet. Specifically, 1-5 feet.

Positive sides

  • Transmit higher amount of energy.
  • Efficiently applicable for communication within a building (metallic building) for shorter wavelength.

Negative sides

  • Can’t travel longer distance.
  • Can’t penetrate most of the obstacles.

VHF (Very High Frequency)

VHF allows longer wavelength in comparatively shorter frequency. The optimum frequency of it is 130 to 174 MHz. But the allowable wavelength is more than 20 feet. The transmission energy is comparatively low but the greater penetration capability allows it to transmit signals to a fat distance.

Positive sides

  • Very high penetration capability. It can penetrate concrete, brick, glass and most of the building materials for its larger wavelength.
  • A greater distance can travel comparatively easily using less energy.
  • It gets bounced in the ground and after the bounce, it continues its running for the destination. So, earth curvature causes comparatively lesser impact in its transmission.

Negative Sides

  • Like most of the waves, VHF can't penetrate metallic body or metallic wall. So, if you are in a building having a metallic wall, you can’t communicate even one room to another in the building.
  • For larger wavelength, it can't penetrate even the shorter distance between two metallic bodies.
  • For shorter frequency, its transmission energy is comparatively low.

Combination of these waves in the radio

In your two-way radio, you'll find the presence of two waves simultaneously. Because the application of only one wave makes the activity of your radio greatly limited. The UHF is for shorter but effective communication.

On the other hand, VHF is for longer communication through the obstacle. You can control the domination of the waves by pressing the controlling switch according to your needs.

Steps for perfect adjustment of the wavelength

Step 1 (Adjustment of UHF)

In general, when you are in the home, you are in need of going through this procedure. For doing this, turn around the UHF control button till the frequency gets higher than the balanced level.

You can easily realize the reading of the frequency from the pointer of the UHF reading. The reading of the VHF will automatically get lessened than the balancing state.

Step 2 (Adjustment of VHF)

Needed to communicate to the further destination. The procedure is almost like the above. There is also a button for controlling VHF in your radio. Turn around it to have the optimum frequency (130 to 174 MHz).

Then you’ll get the perfect adjustment of frequency. When the frequency will fall, the wavelength of the VHF will rise automatically. Along with this, the frequency of UHF will also get balanced.


In fine, the frequency set-up of your two-way radio is nothing but the function of UHF, VHF and the curvature of the earth. Hence, avoiding the obstacle and staying horizontally straight to the signal tower will be the main deed for you. But in the practical sense, maintaining this is quite impossible. So, to get the best possible frequency from radio, you'd better rely on maintaining the perfect combination of UHF and VHF.

Richard B. Torres

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