This equipment specially designed by Netherlands PTT for monitoring the solar flares. It is connected to the Coudé refractor in such a way that as soon as the 545 MHz receiver registers a solar flare, the camera attached to the Coudé refractor automatically starts taking picture every two minutes. Unfortunately, due to oldness and some technical reasons (especially spare parts problem) this system is now out of use.
The telescope consists of two broadside arrays mounted equatorially, so that only a constant movement around polar axis is sufficient. The 545 MHz array consists of 8 full-wave dipoles, spaced with 1/2 wavelength and placed at 1/4 wavelength above a reflecting screen. The 200 MHz array is similar to that for 545 MHz array, except that consists of two full-wave dipoles only. The two arrays are placed perpendicular to each other. The reflecting screen has bars at 1/10 wavelength spacing in the directions of the respective dipols.
Highly stabilized 200MHz and 545 MHz receivers, including RF amplifiers, local oscillators, mixers, IF amplifiers, detectors, DC circuits.
The amout of radiation received from the sun is displayed on two continuous-balanced chart recorders. For calibration purposes two noise generators (at 200 and 545 MHz) are available. There is also a timing unit to record the obsevation time. It shortcircuits the recorder input in every desired time interval.