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reading capacitor value from code printed on it?

Any chance that it is actually 104 rather than 1C4 - if so, it may be an 0.1 uF capacitor - very common value for power supply bypass capacitors.

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Peter Bennett, VE7CEI  
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Reply to
Peter Bennett
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I have a circuit board with a capacitor that needs replacing (it got burned when an adjacent triac went out). The capacitor is a small "bead" shape, and has the code:

1C4 ME5

printed on it.

I can't find anything on the web about this particular code format - can anyone help me figure out what its value and max voltage is?

The circuit has another one of these capacitors, and I thought about pulling it and trying to test its value. My idea is to charge it up to a known voltage, and time how long it takes to discharge through a known resistor. My problem is that I don't know what the impedance of the DVM voltmeter is, and this will influence the discharge rate due to its parallel resistance. Any ideas on how to approach this? I guess I could do this experiment twice, using two different known resistor, and back out the meter resistance. Any better ideas? I don't have easy access to any good electronics bench equipment, so am looking for simple approach.

BTW, I could post a digital closeup photo of the capacitor if that would help.

Thanks.

Bill Christens-Barry

--
Wm A Christens-Barry, PhD
Equipoise Imaging, LLC
equipoise1@verizon.net
http://www.eqpi.net/eqpi/
Reply to
Bill Christens-Barry

"Bill Christens-Barry" skrev i melding news: snipped-for-privacy@news.verizon.net...

Best sugestion: Go buy a capacitance meter.

Second best suggestion: Build an oscillator that make use of _one_ capacitor. It's important that you are able to calculate the oscillation frequens for that particular oscillator. You have an formula f = (r, c). Turn this into c = (f, r). Example:

formatting link
page 8. The formula should be like this: T = 2 * R1 * C1 * ln( 1 + ( 2*R2/R3 ) ) ( T = 1/f ) Turning the formula to calculate C: C1 = T / ( 2 * R1 * ln( 1 + ( 2*R2/R3 ) ) )

Hope this helps : )

Geir

Reply to
Geir Klemetsen

Yes, that turned out to be the answer! Careful inspection showed that some of the paint had chipped off.

Thanks.

--
Wm A Christens-Barry, PhD
Equipoise Imaging, LLC
equipoise1@verizon.net
http://www.eqpi.net/eqpi/
Reply to
Bill Christens-Barry

"Bill Christens-Barry" skrev i melding news: snipped-for-privacy@news.verizon.net...

Best sugestion: Go buy a capacitance meter.

Second best suggestion: Build an oscillator that make use of _one_ capacitor. It's important that you are able to calculate the oscillation frequens for that particular oscillator. You have an formula f = (r, c). Turn this into c = (f, r). Example:

formatting link
page 8. The formula should be like this: T = 2 * R1 * C1 * ln( 1 + ( 2*R2/R3 ) ) ( T = 1/f ) Turning the formula to calculate C: C1 = T / ( 2 * R1 * ln( 1 + ( 2*R2/R3 ) ) )

Hope this helps : )

Geir

Btw: This is second time i post this message. It doesn't show up in the news-group after the first time I posted it.

Reply to
Geir Klemetsen

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