The McMichael 471 was my second ever restoration. It’s a 5 valve superhet with MW, LW and two shortwave bands. It is mains powered, has a big tuning display and a ‘magic eye’ tuning indicator.
The internals of the radio are organised as two chassis, one for the receiver and another for the power supply. This probably to allow the same technology to be re-packaged in a differing cabinet styles.
It also made it very easy the restore and test the power supply independently.
This radio was in very good condition. It must have been kept away from damp all of its life. There wasn’t any corrosion anywhere, just the usual perished rubber wiring and a thick layer of dust.
As per standard restoration procedure, the PSU transformer was checked over, the voltage selection socket needed a bit of work to make contact. A new twin 32uf electrolytic capacitor was installed.
At this point, the PSU was tested.
Power supply with rectifier tube removed and old electrolytic in situ
The radio chassis had all of it’s wax capacitors replaced, all of the resistors were in spec. All of the valves tested ok (their heaters were ok)
Finally all valves were replaced and some testing carried out. One of the IF amplifier tubes had failed conductive coating so this was replaced with a new old stock part.
The magic eye was also worn out, so this was replaced with a new old stock item.
Video of the radio working
Close up of the magic eye tuning indicator