The neutron supermonitor 4-NM-64 with control of the long term stability of measurement

The properties of a neutron supermonitor were investigated from the point of view of long-term stability and the comparability of measurement. The special unit controlling the whole apparatus is described. With the help of the unit, the counting rate in the individual channels, the contents of the multiplicity counters together with the time information, values of barometric pressure, the high voltages applied to the proportional counters and values of the discrimination levels on the preamplifiers are recorded on paper tape. (author)