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Digital multimeter, downloaded from Web

In digital multimeter, there is a transistor-check function, and there is a term hFE. I do-not know how-to use-it, however, different Websites say it is a measurement transistor's gain ("the ratio of the Ic/Ib") such as: https://www.quora.com/What-does-hFE-mean-on-a-multimeter ;etc. .

But I want to know, what-is the full-form (full-NAME) of hFE?

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    \$\begingroup\$ Useful search term : h-parameters \$\endgroup\$ – Brian Drummond Jun 12 '16 at 16:59
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    \$\begingroup\$ Or just look for "transistor Beta". \$\endgroup\$ – Tom Carpenter Jun 12 '16 at 17:06
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    \$\begingroup\$ Related: Why are h-parameters used? \$\endgroup\$ – SamGibson Jun 12 '16 at 17:09
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It is a mouth-full to say as a full name. I found this description here.

hFE is an abbreviation, and it stands for "Hybrid parameter forward current gain, common emitter", and is a measure of the DC gain of a junction transistor. So on a multimeter, it indicates a mode where the meter can measure (probably crudely), the HFE of a transistor.

EDIT: When I talk about transistor gain with other engineer's, we often use the term 'beta', yet in a datasheet 'hFE' is normally what is used by the manufacture based on calibrated equipment for a standalone transistor.

For some transistors hFE readings may be done at several crucial frequencies as well as DC. 'Beta' is a better term for common-base designs, or just a general statement about DC and/or AC current gain in a known circuit.

As a refinement of the original answer, @carloc mentioned that a 'hFE' spelling refers to a DC signal of relatively large amplitude, while 'hfe' refers to a small signal measured deferentially around some common bias point. No specific thresholds were given, though my original answer refers to 'hFE', the DC gain of the transistor.

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  • \$\begingroup\$ May-be mouthfull... I always try to know the full-forms because the full-names commonly "explain" or "define" ownslfs, or at-least "tell" some thing. Thanks. \$\endgroup\$ – Always Confused Jun 12 '16 at 18:04
  • \$\begingroup\$ You may wish to add the hFE (capital F and E) is DC large signal measured, while hfe (small f and e) is small signal differential around some bias point. \$\endgroup\$ – carloc Dec 7 '17 at 22:09
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I'm not sure if I'm understood correctly the question; You want to know the meaning of "F" and "E"?
H is for Hybrid (parameter), F meaning Forward (current amplification) and E is for common Emitter configuration.

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  • \$\begingroup\$ Yes I asked what is "h", "F", and "E" \$\endgroup\$ – Always Confused Jun 12 '16 at 17:10
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    \$\begingroup\$ Ok, I'm not mentioned H (added now) but also Sparky256's reply explain it. \$\endgroup\$ – Antonio Jun 12 '16 at 17:45
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In simple terms it runs a small current fron base to emitter and measures how many times greater the resulting collector to emitter current is. This is the DC amplification or DC beta. Besides a crude test to see if the transistor is working it is useful in DC awitching circuits. For AC beta they measure amount of change in collector current resulting from a change in base current.

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protected by Community Dec 13 '18 at 12:40

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