[cmjones01]

Progress, in the odd spare minute here and there. The wiring to the oven was totally crusty. The little PCB inside which holds the components of the thermistor bridge was in surprisingly good condition. Both capacitors check out fine, just one resistor (600 ohms) was reading nearer 700 so I replaced it. One resistor is marked in the service manual with the value '442' but mine has 1k fitted, according to its markings and my measurement, so I left it alone. It's in series with the adjustment pot anyway.

Repairing the element and attaching new lead out wires was fiddly. The wire (nichrome?) wouldn't take solder whatever flux I used. After some experiments I settled on using the crimp sections of Molex 'KK' inserts to attach bits of (copper) resistor leg on to the broken ends of the element, then looped and soldered the resistor legs together, insulating the resulting bundles of joy from the aluminium oven with silicone-fibreglass heatsink pad. Using the crimp tool on short lengths of rather brittle element wire was a bit trying.

The same technique worked for attaching new silicone rubber insulated lead out wires. The crimps were insulated with heatshrink and then supported with lashings of Kapton tape.

The next move is to fit a DS18B20 temperature sensor in a sensible place.

The EEVBlog thread shows a very impressive complete rebuild of the oven. I'm not going that far, just doing the minimum necessary to get it working reliably for another 30 years or so. Pictures of the rewiring are attached.

Chris