Thread: Bush A.C.91
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Old 24th Jun 2017, 8:09 pm   #177
ms660
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Default Re: Bush A.C.91

All the valve voltages are best taken with respect to chassis, so -ve probe on the chassis and measure the different voltages with the +ve probe.

Note that the voltages shown in the manual were measured with an AVO Model 7 meter, that meter has a low OPV (Ohms Per Volt) compared to more modern meters, can't remember offhand what the OPV was but probably somewhere around the 500 or 1000 ohms mark, the later AVO's had an OPV of 20,000 ohms, a typical digital meter would have a fixed input impedance of 10,000,000 ohms.

Typically 33uF and 15uF for the electrolytics at 400 or 450 volt working, plenty to choose from, radial, axial etc.

Lawrence.

Last edited by ms660; 24th Jun 2017 at 8:19 pm.
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