Left: GMRT 240 MHz grey-scale image of A 1682 with 610 MHz contours overlaid. The 240 MHz image is the same as Fig. 6, right-hand panel. The resolution of the 610 MHz image is 6.2′′ × 4.1′′, p.a. 61.2°, the 1σ rms in the image is 25 μJy beam^-1, the first contour is 0.1 mJy beam^-1, and contours are spaced by a factor of 4. The inset in the bottom right corner is the 1.4 GHz VLA-A image of the central BGC at the resolution of 1.1′′ × 1.1′′. Contours are spaced by a factor of 2 starting from 0.15 mJy beam^-1. Right: spectral index image of A 1682, with GMRT 240 MHz contours overlaid (resolution 12′′ × 10′′, p.a. 60°) The first contour is 3 mJy beam^-1, contours are spaced by a factor of 4. The spectral index scale ranges from light green () to violet ().