Item (#38)

Type
  1. Electrical
  2. Other electrical
Brand Panasonic
Model - / -
Serial 540G620430428011200287
Colour White
Description

HIGH VOLTAGE WARNING
DO NOT ATTEMPT REPAIR IF UNSURE

countertop microwave oven
Other repairs
No other repairs for this item

Repair (#41)

Status Requires parts to repair
Location Yuhua
Date 22 May 2025
Faults

No common faults selected

Problem description

loud noise and smoke when operating microwave. does not heat food item.

Photos

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Repair Notes

replaced mica sheet by bending it slightly and pulling it out

yew#2 on 19 Sept. 2025

took out the magnetron and saw it has burn marks at the emitter end. need to replace it.

yew#2 on 19 Sept. 2025

discharged capacitor to render appliance safe.
tested magnetron, no short/resistance between lead and housing
tested hv capacitor, 1.01uF (within spec)
tested hv diode using 9v battery, it's fine, conducts only in exactly 1 configuration

microwave hv circuit troubleshooting guide:
https://m.facebook.com/photo.php?fbid=10225161053684811&vanity=1574051336

magnetron testing:
https://www.youtube.com/watch?v=gplUW0x_Tsk

diode testing:
https://www.youtube.com/watch?v=ETzJgIgQZjM

visual inspection of mica sheet has severe burn marks, it might be damaged. suggest replacing it as the next step since hv circuit looks fine otherwise.

yew#4 on 23 May 2025