A number of maintenance operations have recently been performed or are still to be achieved on the radiotelescope :
The branches of the trees invading the antenna plateform, as seen on the pictures, have been cut in order to free the space around the antenna and let it move freely in any directions !
A three phase 380 Volts power cable and an Ethernet cable have been routed underground from nearby red building Folie N4 to the radiotelescope. These cables are providing power supply to the antenna motors and remote communication link to electronic devices.
After thirty years the coaxial cable needed to be replaced by a new low loss cable !
We inserted a preamplifier and a pass-band filter into coaxial pathway located in radio rack on antenna plateform.
Not less than three RapsBerry Pis computers are used for controling the antenna movements, receive radiosignals and provide accurate time via GPS receiver.
A second preamplifier that was first inserted for additional amplification was then removed when we discovered that an amplifier was already present on the top of the reception chain, close to the dipole antenna. This amplifier had been design 33 years ago and is still working as soon as a power supply is providing 12 V through the coaxial cable.
The radiotelescope is remotely driven by astronomy client software in order to aim it at a target from which we want to record radio signal. Two applications are generally used : Stellarium et Cartes du Ciel (Skychart). We are developing a driver that connects client application and drives interface board controling the antenna motors.
Interface had been designed by KK6MK and F1EHN. However it was not well adapted to drive our radiotelescope. This is why Patrick F1EBK and Alain F1CJN have designed a new interface board using an Arduino micro controler and with much more control possibilities.
Prototype board and Arduino firmware are working. A PCB version is going to be manufactured. New interface is fully compatible with former KK6MK-F1EHN interface board both for connector and software remote control. However it has more control lines suitable for complete radiotelescope remote commands.
While motors are being repared, we designed a telescope simulator version 2.1 with a nano PC RaspBerry Pi equipped with a 32 bits serial to parallel HAT. A software is simulating parabol movements by setting both 12 bits opto coders values. Written in C language it is using curses library for color text display.