42. Signal - What are the minimum viable SNR, signal strength and signal quality values for watching TV?

Signal quality is the number between 0 and 100, displayed on the info bar when you change channels or when you press the info button on the remote control. Signal strength and SNR values are displayed during a channel scan and also in the signal meter. In order to show the signal meter, press the Zap button on your remote and select the last option on the Quick Menu.

SNR or Signal to Noise Ratio is the most important signal attribute for a good viewing experience. Typically, video starts to break below an SNR of 20dB. Since SNR can vary over time it is best to have a typical SNR of at least 26dB to give yourself some headroom.

Signal strength is measured in dBm and typically ranges from a low of around -86dBm to a high of +6dBm. We test all ZapperBox receivers to work with a signal as weak as -86dBm. However, in order to allow headroom for signal strength to vary, we recommend a typical signal strength of at least -60dBm.

The signal quality number is a value we compute to show an easily understandable signal attribute that ranges from 0 to 100. We weigh it heavily in favor of SNR. A signal quality value of at least 45 is typical for being able to watch TV.