Measurements of the brightness temperature of the radio background over a range of declinations at frequencies of 13.15, 17.5, and 81.5 MHz are described. Geometrically scaled aerials having beamwidths of 17° × 12° and 53° × 12° have been used, and the results are compared to deduce the spectrum of the background between these frequencies. The observed variation of the spectral index across the sky is fitted by a model in which the galactic contribution has temperature spectral indices 2.38 ± 0.03 and 2.46 ± 0.04 for two different regions of sky, superimposed upon an isotropic background due to radio galaxies, amounting to 30° ± 7°K at 178 MHz. The galactic contributions are considered to be associated with radiation from the local spiral arm and from the inter-arm region, respectively. The results are compared with those of other workers at 26.3, 38, 81.5, 178, and 404 MHz. In both regions, straight galactic spectra are found between 13.15 and 178 MHz, with temperature spectral indices 2.38 ± 0.02 and 2.45 ± 0.03. Both spectra steepen appreciably by 404 MHz, and it is concluded that the magnetic field strengths are very similar in the two regions. It is suggested that a change in the dominant production mechanism of cosmic ray electrons takes place at energies in the region of 3 GeV. The observed energy spectrum of primary cosmic ray electrons is shown to be consistent with that deduced from the new radio data.