Accuracy Component Tester.

[caps]

Hi all
Who was interested in what the measurement accuracy in the transistor tester?
In my opinion, it’s not very bad,at about 1%.

 

[caps]

Resistor 1 Ohm 1%.

 

[caps]

0,1 Ohm 1%.

 

[ratstar]

1% error sounds really great until your talking about pico amps, then its 0.00001% accuracy required i think.

 

[(*steve*)]

Why? My picoammeter is around a couple of percent accurate. It works fine.

I think you misunderstand what accuracy means.

 

[BobK]

Um... A 0.1Ω resistor read as 0.11Ω is off by 10%. To be 1% it would have to be between 0.099 and 0.101.

The error has to be calculated as a percentage of the correct value.

Bob

 

[caps]

To be 1% it would have to be between 0.099 and 0.101.

In order to measure 0,101Ohm, it lacks resolution.

 

[caps]

Precision resistor 0,01 Ohm 1%.

 

[BobK]

In order to measure 0,101Ohm, it lacks resolution.

You cannot have more accuracy than you have resolution. But the reverse is not true.

In your 0.01 example, if it can only display the 1/100 digit, the true measurement might be anywhere from 0.0005 to 0.015 and it would display 0.01. So the precision is about 50%

Bob

 

[Ratch]

Hi all
Who was interested in what the measurement accuracy in the transistor tester?
In my opinion, it’s not very bad,at about 1%.

What parameter of the transistor is the transistor tester measuring?

Ratch

 

[(*steve*)]

What parameter of the transistor is the transistor tester measuring?

Resistance :-?

 

[Ratch]

Resistance :-?

Don't think so. The resistance of a semiconductor varies with the voltage of the ohmmeter. It does not follow Ohm's law.

Ratch

 

[(*steve*)]

Don't think so. The resistance of a semiconductor varies with the voltage of the ohmmeter. It does not follow Ohm's law

Exactly.

We haven't seen any measurements you'd typically associate with a transistor.

But I know these devices do them.

Of what they test, I'm not sure you need any particular level of accuracy. Even if you want to find closely matched devices, all you need is something which produces repeatable (and possibly reasonably precise) results, not necessarily highly accurate ones.

 

[kellys_eye]

Personally I'd use a resistance meter to test a resistor and leave 'that' particular test device for what it was originally intended - semiconductors.

 

[Ratch]

Personally I'd use a resistance meter to test a resistor and leave 'that' particular test device for what it was originally intended - semiconductors.

The OP wrote "transistor tester". Perhaps he meant transistorized tester (ohmmeter).

Ratch

 

[Ratch]

Exactly.

We haven't seen any measurements you'd typically associate with a transistor.

But I know these devices do them.

Of what they test, I'm not sure you need any particular level of accuracy. Even if you want to find closely matched devices, all you need is something which produces repeatable (and possibly reasonably precise) results, not necessarily highly accurate ones.

Too bad this testor is not manufactured anymore. It did a quick check on a transistor by determining if it could invert a pulse. http://www.cbtricks.com/miscellaneo...ore_tf26_cricket_full_sm_with_corrections.pdf

Ratch

 

[kellys_eye]

The OP wrote "transistor tester". Perhaps he meant transistorized tester (ohmmeter).

Ratch

Nope, the screen (LCD) display is that of one of those cheapo Chinese 'multi-tester' devices.

 

[Hopup]

I myself have one of these cheap meters and it is pretty useful, have not used it for transistors other than initial testing of the device. They should be able to detect Hfe, Ube and other parameters, but if I remember right, the results were not very good.

 

[caps]

What parameter of the transistor is the transistor tester measuring?

Ratch

Resistance.

 

[caps]

Precision resistance.
1,8к 1%.
3,16к 0,1%.