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Decent multimeter - Alan Ashton - 15-01-2019
Anyone recommend a decent meter? Would a second hand Avo be worth the money?
Alan
RE: Decent multimeter - Reckless Rat - 15-01-2019
I have had a cheapo multimeter (analogue not digital) since time mint imperial and it's still even on the original batteries. Unless you're using it every day then buy something reasonable from the Bay of E.
RE: Decent multimeter - bob46320 - 15-01-2019
What do you want to measure? If its just car related stuff like DC volts, perhaps current up to 10 amps, resistance and continuity, a 5 pound analog job off the market. If you want to to measure things more accurately, a Digital meter for 15 pounds and upwards, but I find an analog meter is the best for the Austin's 6 volt system because it gives a better average voltage at 6 volts DC whereas the DVM is flying up and down and what does 0.1 volts mean with a dynamo system anyway. I carry a cheapo analog meter in both my old cars.
Ps - an old AVO would take almost as much space as the 6 volt battery !!
RE: Decent multimeter - Mark McKibbin - 15-01-2019
(15-01-2019, 12:36 PM)Alan Ashton Wrote: Anyone recommend a decent meter? Would a second hand Avo be worth the money?
Alan
I have several cheap digital ones and they are rubbish on a car as there is too much interference and they read all over the place however I also have a Fluke Digital and that always reads correctly I do have an Avometer but it is too cumbersome.
Honestly I do most fault finding with a test light as you can make some really bad assumptions with a digital or any meter with a high input resistance (like a FET analogue meter).
RE: Decent multimeter - Bob Culver - 15-01-2019
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.
RE: Decent multimeter - Terrytuned - 15-01-2019
(15-01-2019, 12:36 PM)Alan Ashton Wrote: Anyone recommend a decent meter? Would a second hand Avo be worth the money?
Alan
Alan if you want a decent Automotive dedicated meter have a look at a Sealey TA302 it does most automotive tests and does not suffer from digital interference as all of the cheaper meters do. Terry.
RE: Decent multimeter - Chris KC - 15-01-2019
Depends how much you plan to use it and what for I guess Alan. I had a cheap digital one off eBay and it has done all I required of it A7-wise; which I grant you was not much.