15-01-2019, 05:04 PM
The calibration tolerance of analogue meters is a % of full scale. Even a super expensive large AVO new was not great.
Digital do not handle well spiky or erratic waveforms, such as the pulsed output from an electromechanical regulator.
High ohms per volt was necessary for old radio and some digital work but completely unnecessary for original Seven. It is largely the feature that you paid for in quality analogue. Digital far exceed the best analogue in ohms per volt but actually a disadvanatge as responds to static like electricity. The radio radiation from an unsuppressed ign system as Seven sends digital haywire (although a resistor/capacito across input may cure)
Digital measure low and very low ohms, handy for diagnosing armature faults, if into such things. Cheap analogue dont.
Even the cheap digital claim high accuracy.
For analogue a very basic will suffice. If you hit volts on the ohms range and wreck it no great losss. Only need batteries for the ohms range.
Very exact volts is useful if do a lot of battery charging, or setting of regulators on other old models.
A digital can be used to calibrate analogue. (and your cheap digital checked against someone elses, esp if they have an expensive digital). Accuracy really only critical in the car battery volt range.
Digital very convenient to read battery charge volts, where .2v important
Like modern cameras, digital dont work when the quite expensive battery flat (and can be inaccurate when it dieing)
For non digital circuitry, as mentioned much can be done with a test lamp. It will pick up high resistance connections which a meter may not immediately. A good use for old double fil lamps where one burned out. An old headlight bulb will test a dynamo for output more effectively than fancy meters.
Digital do not handle well spiky or erratic waveforms, such as the pulsed output from an electromechanical regulator.
High ohms per volt was necessary for old radio and some digital work but completely unnecessary for original Seven. It is largely the feature that you paid for in quality analogue. Digital far exceed the best analogue in ohms per volt but actually a disadvanatge as responds to static like electricity. The radio radiation from an unsuppressed ign system as Seven sends digital haywire (although a resistor/capacito across input may cure)
Digital measure low and very low ohms, handy for diagnosing armature faults, if into such things. Cheap analogue dont.
Even the cheap digital claim high accuracy.
For analogue a very basic will suffice. If you hit volts on the ohms range and wreck it no great losss. Only need batteries for the ohms range.
Very exact volts is useful if do a lot of battery charging, or setting of regulators on other old models.
A digital can be used to calibrate analogue. (and your cheap digital checked against someone elses, esp if they have an expensive digital). Accuracy really only critical in the car battery volt range.
Digital very convenient to read battery charge volts, where .2v important
Like modern cameras, digital dont work when the quite expensive battery flat (and can be inaccurate when it dieing)
For non digital circuitry, as mentioned much can be done with a test lamp. It will pick up high resistance connections which a meter may not immediately. A good use for old double fil lamps where one burned out. An old headlight bulb will test a dynamo for output more effectively than fancy meters.