Restoration methodsWorkshop HintsChecking Filter Condensers![]() Checking Converter OperationConnect a voltmeter of suitable range between the B plus connection of the oscillator coil and chassis, i.e., across the bypass capacitor, and short circuit the oscillator section of the gang condenser to chassis. A reduced reading on the voltmeter indicates that the oscillator section is working.The reason for the reduced reading is that bias across the oscillator grid leak is removed by shorting the gang. This in turn causes the triode section to draw more current, thus resulting in a greater voltage drop across the oscillator plate dropping resistor Curing OscillationFrequently in circuits where persistent oscillation occurs and which cannot be traced to any circuit fault, it is possible that the various coil shields etc, are not as effective as they should be.Where this fault is suspected, it is well worth the time and effort to remove these shields and tighten the rivets holding the spade lugs, which are used to hold the can to the chassis. Add comment:
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