Vbw

VBW is an acronym with multiple meanings, but in electronics and signal processing it most often denotes video bandwidth. The term is commonly used in measurement instruments and video systems, and it can describe a specific filtering parameter applied to the signal path. While other uses of the acronym exist in different fields, the electronic meaning is the best known in technical contexts.

In test equipment such as oscilloscopes and spectrum analyzers, video bandwidth refers to the portion of the signal path that is allowed to affect the displayed video signal. It is typically implemented as a low-pass filter after the detector or digitizer, reducing high-frequency components to produce a readable trace. The VBW setting thus shapes the balance between display clarity and fidelity to fast signal details.

The effect of VBW on measurements is one of trade-offs. A higher VBW preserves sharp edges and fast transients but also increases display noise and may reveal high-frequency content that is not representative of the underlying signal. A lower VBW smooths the trace, reduces noise, and helps visualize slower signals, but it can blur rapid events and slightly distort peak values. Importantly, VBW controls the displayed result rather than the instrument’s true input bandwidth, so users must distinguish between what is displayed and what the signal itself contains.

In practice, VBW is adjusted to balance temporal resolution and noise, often alongside other controls such as time base and vertical scaling. The exact meaning and range of VBW are device-specific.