You might find your way to Roku’s Wireless Secret Screen to find that Antenna 2 is showing a value of zero.
Does 0 signal strength mean the Roku device is broken?
The answer is No. Read on to find out more.
Roku has a number of streaming devices on the market. All of them support Wi-Fi connectivity.
However,
- the Roku Express 3930CA only supports 2.4 GHz band
- the Roku Express 4K 3940CA supports both 2.4 GHz and 5 GHz Wi-Fi.
Since the Roku Express supports only a single 2.4 GHz frequency band with the 802.11 b/g/n standard, it only has one antenna. This is why Antenna 2 is reporting a power level of zero (0), while Antenna 1 is showing a non-zero power level.
The Roku Express 4K and other products including Streaming Stick, Streambar and Ultra support both 2.4 GHz and 5 GHz bands. Therefore they have two internal antennas – one for each band. The secret screen will therefore report power levels for both antennas.
What does frequency band mean?
A Frequency Band is a specific range of frequencies within the electromagnetic spectrum that is used for various communication applications. Different frequency bands are used for different purposes, such as Wi-Fi, amateur radio, microwave communication, and FM broadcast.
The International Telecommunication Union (ITU) has allocated certain frequency bands specifically for Wi-Fi usage. These are in the 2.4 GHz and the 5 GHz range.
Specifically the 2.4 GHz band extends from 2401 MHz to 2495 MHz. The 5 GHz band covers 5150 MHz to 5895 MHz. Wikipedia Reference.
The 2.4 GHz band is commonly used and offers a broader coverage area, but it is more susceptible to interference from other devices such as microwaves or Bluetooth devices.
On the other hand, the 5 GHz band provides faster data transfer rates due to its less crowded nature and wider frequency range. However, it has a shorter range and may face more obstacles in signal transmission. WiFi devices are designed to operate within these predefined frequency bands, allowing for efficient wireless communication between devices.
Why is a different antenna required for each frequency band?
The physical dimensions of an antenna depends on the frequency range it was designed to cover. An antenna for 2.4 GHz will be larger than one designed for 5 GHz. A single antenna cannot be used for both frequency ranges.
Use the Dipole Antenna Length Calculator to find the difference in lengths between 2.4 GHz and 5 GHz antennas.
| Frequency (MHz) | Antenna Length (inches) |
|---|---|
| 2450 | 2.29 |
| 5000 | 1.12 |
Further reading
- Roku RSSI vs SNR – What do they mean?
- Antenna range calculator – Use this tool to study the impact of frequency range on signal propagation. What’s the difference in distance covered for 2.4 GHz vs 5 GHz Wi-Fi?