M.Ing. / The main contribution of this thesis can be summarized as follows. Firstly, we implemented a high speed error gap recording system, which can run with at most with a slight adaptation, on any personal computer, doing gap recording for digital communication systems, achieving a data rate of up to 200 kbits/sec. Secondly, we extended previous experimental investigations of the Fritchman channel model to three other channel models, namely the Gilbert, Gilbert-Elliott, and Aldridge- Ghanbari models, and implemented these models experimentally by a set of computer programs. Thirdly, we investigated the statistical modeling of two analog channels, employed for digital transmission. These are an analog audio cassette, magnetic tape recorder and an analog cordless telephone operating in the 46/49 MHz. band, in the CT1 system. No evidence could be found in the literature of modeling error distributions on these two channels.