JMA-5300MkIIsm

INDEX > 4.Replacement Procedure > 4.3 Scanner Unit NKE-2254 (JMA-5322-7/9/6HS)
Use a non-magnetic secrewdriver because the contact of the metal tool with the
magnetron causes deterioration of its performance.
4) After having replaced the magnetron, reassemble the unit by following the disassembly
procedure in the reverse order.
Do not forget to tighten the screws and connect the cables.
Extreme care should be taken to connect the leads (yellow and green) to the magnetron
for prevention of contact with other parts or the casing. Contact may cause them to
discharge.
4
[Check points]
1) Turn on the power supply for the radar. Allow sufficient time for the radar to be
preheated (about 20 to 30 minutes / bring the radar unit to STBY mode).
2) Start emitting radio waves from the short pulse range and gradually change the
emissions to the long pulse range. Open the serviceman menu to perform tuning
adjustment (Refer to Section 7.1.4 of the instruction manual).
If operation becomes unstable such as the magnetron current is unstable (see Section 6.1.1,
page 6-1), bring the radar unit back to STBY mode and restart emission after allowing for an
interval of 5 to 10 minutes.
3) Emit radio waves in long pulse range mode (48NM) for about 15 minutes and reopen
the serviceman menu to perform tuning adjustment.
Adjust the setting in the serviceman menu until the tuning indication bar on the display unit
reaches the 8th calibration marking.
With the test menu open, also make sure the magnetron current is shown between the 6th and
9th calibration markings.
Finally, initialize the transmission time in the serviceman menu (Refer to Section 7.4.4 of the
instruction manual).
4-27