1. J Error 13 38 V DC supply out of range Check the value with a volt meter on the test point of the Power Supply Board and replace it if the value is not in the range 34 to 42 V. Voltages are Ok , I have measured it and its 36Volts. This error seldom occurs... Q Error 21 No tube current No or low anode current. This error can be caused • by interruption of High Voltage power supply (right side of the Power Switching Unit board) • or by interruption of the filament power supply (left side of the Power Switching Unit board) • or by interruption of the driving circuits (in the regulation board) • or by fault in the tube-head (input transformer or multiplying circuits). Check the supplying circuit in the bushing (multi-pole cable) and the flat cable between the regulation and power switching boards. On the Power Supply unit check the switch SA 301 (must be ON), fuses FU 304 and FU 305. If they are OK, switch exposure and check the driv- ing signals for HV regulator and inverter (points 1, 2, 6 and 7 on the Regu- lation Unit) and the HV inverter supplying voltage (between points D3 and S5 in the Power Switching Unit) – should be in range from 50 to 100 volts (depending on kV and mA setting). Then measure the primary circuit of HV transformer. If all is correct, the circuit between the secondary of HV transformer and tube is broken. Depending on the location of the fault, consider to replace the Power Switching Unit board, the Regulation Unit board, the connecting cables or the tube-head. This error can be also activated by sparking in the tube, when a very short over-current signal switches off the HV regulator only, but is not trapped by the Control Unit in order to activate error 17. In this case try to perform the tube seasoning (de-gassing by making a number of exposures at low kV) or replace the tube-head if necessary. This is difficult to find. I am currently trying to check the cabling.... Any ideas further?