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Projects => How Do I? Beginner's Paradise. => Topic started by: 2tonewarrior on August 01, 2012, 05:51:46 PM

Title: Measuring transistor Hfe
Post by: 2tonewarrior on August 01, 2012, 05:51:46 PM
Another quick transistor question  ;D

Is it possible to test the Hfe of a transistor with a multimeter WITHOUT a transistor test socket? Or maybe with some easy circuit?

Thanks in advance
Title: Re: Measuring transistor Hfe
Post by: mgwhit on August 01, 2012, 06:07:52 PM
R.G. Keen's article Picking transistors for FF Clones (http://www.geofex.com/Article_Folders/ffselect.htm) has a good circuit for measuring PNP Germanium transistors.  It can easily be adapted for NPNs.
Title: Re: Measuring transistor Hfe
Post by: joegagan on August 01, 2012, 09:26:05 PM
the multimeters from harbor freight have hfe testing and trans sockets. they are under 10 bucks, and they seem to give reasonably good readings.

^^^ above was for Si. Ge trans, see the RG article linked above.
Title: Re: Measuring transistor Hfe
Post by: 2tonewarrior on August 02, 2012, 12:27:41 PM
Thanks for the info, Mr. Keen is always present to solve the doubts   :)

I should have bought a good cheap MM when I started with electronics but I bought a bad, cheap MM in a local store. For now I want to make the most out of mine, but IŽll keep the advice for the future.
Title: Re: Measuring transistor Hfe
Post by: Bret608 on August 28, 2012, 11:29:35 AM
My Harbor Freight DMM does seem to give reasonable readings on silicon transistors. I've only tried a couple of germaniums with it, but I can't seem to get a reading.
Title: Re: Measuring transistor Hfe
Post by: icecycle66 on August 28, 2012, 02:38:03 PM
My meter counts backwards to some apperantly unrelated number when I try to measure Hfe.
 
What's up with that?
Title: Re: Measuring transistor Hfe
Post by: murdog47 on August 28, 2012, 06:55:30 PM
You might be interested in one of these

http://www.ebay.com/itm/Multi-Use-Transistor-Tester-Meter-NPN-PNP-MOSFET-diode-resistor-capacitor-/320944953048?pt=BI_Electrical_Equipment_Tools&hash=item4ab9cf56d8#ht_12910wt_1219
Title: Re: Measuring transistor Hfe
Post by: atreidesheir on September 08, 2012, 09:24:03 PM
You might be interested in one of these

http://www.ebay.com/itm/Multi-Use-Transistor-Tester-Meter-NPN-PNP-MOSFET-diode-resistor-capacitor-/320944953048?pt=BI_Electrical_Equipment_Tools&hash=item4ab9cf56d8#ht_12910wt_1219
Nice.