Multimeter application skills needle selection of table and digital table

 1,the read pointer table accuracy is poorer,but the process of pointer swing is more intuitive,the swing speed range can sometimes more objectively reflect the size of the measured (such as TV measurement data bus (SDL) in the slight shaking when transmitting data);Digital intuitive readings,but electricalmotor1.blogspot.com digital change process seems very messy,not easy to watch.2,pointer table usually has two pieces of batteries,a low voltage of 1.5 V,is a high voltage 9 V and 15 V,the black pens and relative red pens and it is the generator generator set end. Numbers were commonly used a piece of table 6 v or 9 v battery. In resistance,pointer table pens and output current is relatively much larger Numbers table,diesel generating can make the speaker in R x 1 Ω gears a loud sound "da",using R x 10 k Ω file can even light emitting diode (LED).

3,the voltage profile,pointer table resistance relatively smaller,compared with digital meter measuring accuracy is quite poor. Some high voltage micro current situation cannot even measure,because of its resistance to affect the circuit being measured (such as when measuring the acceleration of the TV picture tube voltage level measured value is electrical motor lower than the actual value will be many). The integrity of the digital meter voltage resistance is very big,at least in ohms,little impact on circuit under test. But high output impedance makes it vulnerable to the influence of the induced voltage,in place of some strong electromagnetic interference is measured data may be empty.4,all in all,in a relatively large current measurement of high voltage analog circuits pointer table,such as TV sets,audio power amplifier. In the low voltage low current measurement of digital circuit for digital table,such as BP machine,mobile phone,etc. Is not absolute,can choose according to the circumstance pointer table tables and figures.