PENNINGVAC-Transmitters PTR are active sensors (pressure to voltage converters) based on the principle of the Inverted Magnetron technology. Here the pressure is measured through automatic ignition of the cold cathode by the MEMS PIRANI (PTR 90). These sensors offer a wide measurement range (10^-8mbar) and have a very long life time, due to a low ionization current and compact stainless steel body.