A dc glow discharge configuration was investigated that includes a flat semitransparent anode situated between two symmetrically positioned cathodes. The transparency of the anode increases the electron path length for ionizing collisions. This leads to a significant increase in the number of free electrons in the discharge volume. The simplicity of the discharge configuration makes it possible to model the electron avalanche in its early stage with proper boundary conditions and without the use of adjustable parameters in both elastic and nonelastic scattering cross sections. The results obtained for hydrogen indicate that the number of free electrons in the discharge can be increased by several orders of magnitude in comparison with a similar discharge configuration but with an opaque anode.