Is it possible to discover a capacitor's value without clear markings?

Is there some type of measurement I can do with a voltmeter?

I have a small blue cap, with the numbers 104 on the side, and I want use it to set up a parallel RC circuit, to re-create a lab we have done at school.

Thanks,
Gary

 

A LOT of newer DVMs have capacitance meters as a feature, but I don't think that is what you're talking about, is it?

104 is 10000pf, or .01µF.

 

Is it possible to discover a capacitor's value without clear markings?

Yes, it can be measured.

Is there some type of measurement I can do with a voltmeter?

Yes, some methods can use a voltmeter, but not a voltmeter alone. You can use an AC sinusoidal voltage source with an RC circuit. O-scopes are better to use however.

I have a small blue cap, with the numbers 104 on the side, and I want use it to set up a parallel RC circuit, to re-create a lab we have done at school.

OK, good luck! By the way, the 104 is a clear marking of the capacitor value. - Just in case you didn't realize that.

 

Well yes if you had a sufficiently large value resistor, in relation to the capacitor, you could measure the charge and/or discharge with your voltmeter and your wristwatch.

 

Thanks Bill,
I suppose that is what I'm talking about, but I don't have a meter with that ability.

I have an Oscilliscope, a benchtop Fluke meter, and an old Function Generator.

Might I be able to apply a voltage, get a reading, and do some math to help me identify it?

Thanks,
Gary

 

By clear, I meant discernable. I have others that specify their unit of measure, such as 10 micro farad, 50 v, etc.

Do you think that would work with a low voltage?
I'm looking at a 8.78 V ac power supply, with a 4.7K resistor, and a capacitor (I thought the smaller the better?).

Gary

 

Forgive me for not reading Bill's reply completely.

Thanks Bill (and everyone).

I will read and print this off later.

The answer of 1 micro farad is what I needed.

Gary

 

I have an Oscilliscope..

People often forget that a scope can also be pressed into service as a voltmeter, currentmeter, chargemeter, AC or DC...the list is nearly endless.

 

Is there a way to guestimate what components would be necessary to make up a reasonable test circuit?
For example:
My AC Power supply is only 8.78 V AC
The Frequency if 60 HZ
The capacitor is .01 micro farads
The resistor is 4.637K Ohms

In solving, I'm getting some weird answers
XC = 265 K
IR = 1.91 mA
IC = 33.1 micro A
IT = 1.91 mA
Z = 4.59 K
PC = 263 K
PR = 4.59 K
PT = 4.59 K
Phase = 992???
P.F. = 1

What component would work best?
I have a wide range of resistor sizes to choose from, a few capacitors, and not many choices on voltage / frequency?

Thanks, Gary

 

Forgive me for not reading Bill's reply completely.

Thanks Bill (and everyone).

I will read and print this off later.

The answer of 1 micro farad is what I needed.

Gary

You better read it again, the answer given was .01 not 1 microfarad

Lefty

 

104 is 10000pf, or .01µF.

No.
104 is 0.1uF not 0.01uF. 103 is 0.01uf.

10 followed by four zeros is 100,000pF. 100,000pF is 0.1uf.

Why can't the Orientals label it 0.1uF or 100nF instead of 104??

 

Why do you credit Orientals for this convention?