Enraf Nonius Radarmed 650, Service Manual

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Enraf-Nonius B.V. Radarmed 650 Service Manual 1409773
Maintenance January 2000
4-6
in par. 4.5.2.
4.6.1 Magnetron heater voltage adjustment
Switch on the Radarmed 650 unit. Check the mains voltage at the mains distributor strip
CNA (see appendix B fig. 11) between the white wire at connection CNA-1 and the purple
wire at CNA-2, CNA-3 or CNA-4 and check that the mains voltage is
230V ±1V / 50Hz.
Measure the heater voltage directly at the magnetron at the two blue leads. The measured
voltage must be between 3.37V. and 3.43V.
Warning: Do NOT set the treatment time and/or start a treatment. When a treatment
is started high voltage (!! 2000V. with respect to ground !!) is applied to
the cathode of the magnetron (High-Voltage connection is the blue wire
connected to PCB2 - CN4).
If the heater voltage is to low, shift the purple wire to the next higher connection at CNA
(fig. 11), for example: shift the purple wire from CNA-3 to CNA-2.
Shifting the purple wire from CNA-4 to CNA-3 or CNA-2 will increase the heater voltage.
If the heater voltage is to high, shift the purple wire to the next lower connection at CNA
(fig. 11), for example: shift the purple wire from CNA-3 to CNA-4.
Shifting the purple wire from CNA-2 to CNA-3 or CNA-4 will decrease the heater voltage.
4.6.2. H.F. output power adjustment (using a moving-coil milliammeter in the DC range)
Warning: Be careful, high voltage (!! 2000V with respect to ground !!) is present
during the anode current adjustment.
The following power adjustment refers to the use of a moving-coil milliammeter in the DC
range and a large (150 W) emitter for the 100 W adjustment.
On the magnetron / H.F. filter assembly the anode current of the different output power
ranges (100W. and 10W.) are found. These values are valid for the magnetron / H.F. filter
assembly in question. These values are factory determined and are measured in the high
voltage cathode lead which is connected to CN4 at the distributor PC Board
(see appendix B, fig. 7).
If no emitter is connected ®
) "000" appears in the output power display and the
appliance cannot be started.
Connect a large emitter to the output connector of the unit.
Plug the voltage selector jumper CN3 (distributor PC Board) onto CN6 high-voltage tapping.
Connect the moving-coil milliammeter in the cathode lead at connector CN4 at the distributor
PC Board. Using a mains voltage of 230V. / 50Hz, turn the output power control fully anti-
clockwise and than clockwise until the H.F. output power display reads “100".
Check that the current value read on the milliammeter correspondents to the value which is
found on the magnetron/filter assembly for 100 Watts H.F. output power.
If the value is not correct find the nearest value by changing the high voltage supply by
making one of the following combinations on the distributor PC Board:
Connect CN3 to CN2 supply voltage: 1900V.
Connect CN3 to CN6 supply voltage: 2000V.
Connect CN2 to CN8 and CN3 to CN11 supply voltage: 2100V.
Connect CN6 to CN8 and CN3 to CN11 supply voltage: 2200V.