A systematic investigation of excited Q+ states in 202,204,206,208Pb is carried out by means of in-beam conversion-electron and gamma-ray spectroscopy. Several new Q+ states and EO transitions are reported. The measured quantities include transition energies, half-lives, X- and ρ2 values. The results are discussed in view of the published shell model calculations and intruder-states systematics. A comprehensive evaluation of the K/L ratios of EO transitions is presented. The experimental developments cover, among other things, high-energy electron spectroscopy, new, controversial results concerning detection efficiency of electrons by a semiconductor detector and a revised approach to data analysis of electron spectra. A new compilation of several useful calibration sources for gamma-ray and electron spectroscopy, based partially on present measurements, is included.