Total flux density of VHS 1256−1257AB from VLA observations updated with our new data and with published data (Guirado et al. 2018) on a smaller bandwidth sampling (circles). Different colors indicate different bands: 1.4 GHz (red), 6 GHz (yellow), 10 GHz (green), 33 GHz (blue), 230 GHz, and 345 GHz (gray). 3σ non-detections are plotted as arrows. Lines represent different gyrosynchrotron models with δ = 1.36 (see Sect. 5.3.1): dotted line for localized emitting region at the stellar surface with size of 1 R_* (LES1) and dashed and dash-dot lines for radiation belts with B₀ = 2000 G (RB2) and B₀ = 3000 G (RB3), respectively.