# transistor tester?



## lcipher3 (Jan 9, 2020)

So I have multimeters, scope, etc - anyone have a transistor tester or do you just rig up a circuit each time?
Im talking about some of those you see on ebay for 10-20 bucks.


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## Mourguitars (Jan 9, 2020)

https://www.amazon.com/gp/product/B01MS1FOYM/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
		


A few of us bought this one , seems to work out pretty good. I bought some bad J201's of the bay that tested everywhere ...but the SMD J201's test fine...all in same range

Mike


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## Betty Wont (Jan 9, 2020)

Mourguitars said:


> https://www.amazon.com/gp/product/B01MS1FOYM/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
> 
> 
> 
> ...


That looks interesting. Does it provide leakage details for germaniums?


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## Nostradoomus (Jan 9, 2020)

The one I bought doesn’t do leakage...I bought a Peak DCA55 though so now that one doesn’t really get used.


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## lcipher3 (Jan 9, 2020)

Mourguitars said:


> https://www.amazon.com/gp/product/B01MS1FOYM/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1
> 
> 
> 
> ...



Yeah - that's the one I'm looking at.  Worth it? Not bad?
Is there a pdf anywhere on this model?


Is this the exact same ($5 cheaper-sold by Neoteck ) or did you specifically recommend the one sold by DROK






						Amazon.com: Neoteck Transistor Tester with Test Leads, Mosfet Transistor Capacitor Tester, NPN PNP Transistor Diode Resistor Inductor Capacitance MOS SCR ESR Meter Automatic Checker Detector: Home Improvement
					

Buy Neoteck Transistor Tester with Test Leads, Mosfet Transistor Capacitor Tester, NPN PNP Transistor Diode Resistor Inductor Capacitance MOS SCR ESR Meter Automatic Checker Detector: LCR Meters - Amazon.com ✓ FREE DELIVERY possible on eligible purchases



					www.amazon.com
				





There's also a bunch on ebay (US ship) that look exacly the same - but are they?!


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## Mourguitars (Jan 9, 2020)

I bought the DROK one i went thru my purchase history i guess i payed extra with prime 2 day...i guess for the simple DIY guy like me it works fine.

Someone posted up a Multi meter that had a lot of bang for the buck off amazon a while back that people liked...anyone remember what that was ...my battery leaked in mine or recommend me a nice one ?

Mike


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## chongmagic (Jan 9, 2020)

I use this one, and it works great for me, and won't break the bank.



			https://www.amazon.com/gp/product/B07SHLS639/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1


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## Mourguitars (Jan 9, 2020)

chongmagic said:


> I use this one, and it works great for me, and won't break the bank.
> 
> 
> 
> https://www.amazon.com/gp/product/B07SHLS639/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1



Thats the one !

Thank you CM !


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## chongmagic (Jan 9, 2020)

Mourguitars said:


> Thats the one !
> 
> Thank you CM !


Anytime, a great meter for the price for sure. Lots of features too!


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## lcipher3 (Jan 10, 2020)

So got my transistor tester (the "DROK" Mega328 version above) and it's pretty cool.
Testing a lot of parts - pretty accurate.  Nice little tool

Interesting .... it shows some 2N5484 JFETS as BJT.  
Might have some counterfeits 

Otherwise 2n5457, 2N5088, etc all check out right on.  Even some old P-JFET cans 2N5114


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## Mourguitars (Jan 13, 2020)

chongmagic said:


> I use this one, and it works great for me, and won't break the bank.
> 
> 
> 
> https://www.amazon.com/gp/product/B07SHLS639/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1



Oh man ...i like this Multimeter....


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## chongmagic (Jan 13, 2020)

Mourguitars said:


> Oh man ...i like this Multimeter....



Yeah it is killer for the price right? I love how the lead connectors light up based on the mode you are in to show you what should be connected.


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## lcipher3 (Jan 14, 2020)

Can someone who has one of these testers ("DROK" Mega328 ) check the following:


2N5484  
J201 

ALL of mine (handful) come up as BJT on the tester.  
They may be fakes (esp the 2N5484s) 
The few J201s I have I thought were from a good source (still a possibility of fakes I know)

I just want someone to see what they get with a known "good" one using this tester
OTHER JFETS I have come up correctly (as JFETS)


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## Mourguitars (Jan 14, 2020)

JFETS, matching etc.
					

Ok.. Tayda jfets are jfets.. thats' t the meter probably. Those cheap LCR meters are not the best choice for JFET measuring. I have one and do not use it for jfets because readings are off.  Mourguitars - can you measure the same transistors with this simple setup?   T.  Be damned sure you have...



					forum.pedalpcb.com
				




Here is my readings from the ebay J201's from 2 different sellers when i first started...they are all over the place. Im scared to use them so i went SMD J201's , bought the boards here and the 201's from Tayda but they all specked out what they should be.....busy at work at the moment but ill pull the SMD's i did and give you the readings this evening...if that helps Icpher3

Mike

I think i may have the 2N5484 as well ....i'll test them as well


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## lcipher3 (Jan 14, 2020)

Thanks Mourguitars - looks like what I'm seeing.  Looks like I'll be doing the SMT thing too.


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## Mourguitars (Jan 14, 2020)

Thought i had the 2N5484 but what i have are the 2N5485 but here are the results on the 85's bought a 25 bag off ebay and 5 from Tayda tested with  the DROK :

Ebay bag of 25 i got pulled 8 out of the bag all tested
I=1.9mA
vgs=1.3 v
All 8 tested at that..i rechecked 3 times

Tayda's 2N5485's bought a bag of 5
I=1.9mA   ......1.6.....1.7....1.4......1.8
vgs=1.4v .......1.1.....1.2....0.97....1.2

My SMD J201's using the board i bought here , 201's SMD i got from Tayda ...tested 10
1.61 thru1.63
 .96 all 10

The SMD wasn't that hard soldering...just don't rush....kinda like soldering a flea to a tick lol

Thats the readings im getting off my tester

Mike


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## lcipher3 (Jan 14, 2020)

Thanks - so on your J201s that you tested (from your old link) why do you think some show up as BJT and some as JFET?  Fakes?


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## Mourguitars (Jan 14, 2020)

lcipher3 said:


> Thanks - so on your J201s that you tested (from your old link) why do you think some show up as BJT and some as JFET?  Fakes?



Im sure those were fakes , swept off the floor, mixed ..seconds..who knows ! From eBay..
There still taped to that paper ...not using those lol

I think I did see PedalPCB selling those pre soldered J201s....just buy those if your not into soldering those little SMDs...but I think that way is the way to go personally myself...and maybe in the future for all the hard to find ones

Mike


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## lcipher3 (Jan 15, 2020)

Yeah I'm going to buy some SMT ones and check them - prob get a few of those PCB adapters too.  
Nice to have the meter to check for fakes.  Looks I've already gotten my moneys worth in it.


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## Robert (Jan 22, 2020)

One of those Chinese transistor testers is falsely reporting genuine MMBFJ201s as BJT. 

The DCA75 reads them accurately.


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## lcipher3 (Jan 22, 2020)

Robert said:


> One of those Chinese transistor testers is falsely reporting genuine MMBFJ201s as BJT.
> 
> The DCA75 reads them accurately.



Thanks - yeah, I'm thinking my J201s are legit.  Sourced from Mouser long ago, other reputable sources.
The other 2N5484 - *those* I had trouble measuring decent specs on a breadboad.  Those could be fakes.


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## mywmyw (Jan 26, 2020)

Mourguitars said:


> Im sure those were fakes , swept off the floor, mixed ..seconds..who knows ! From eBay..
> There still taped to that paper ...not using those lol
> 
> I think I did see PedalPCB selling those pre soldered J201s....just buy those if your not into soldering those little SMDs...but I think that way is the way to go personally myself...and maybe in the future for all the hard to find ones
> ...


i havent seen the presoldered j201s back in stock in a while.... Bugg was that mostly a test run, or were you planning to offer more*?*


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## Mourguitars (Jan 26, 2020)

mywmyw said:


> i havent seen the presoldered j201s back in stock in a while.... Bugg was that mostly a test run, or were you planning to offer more*?*



Mr PedalPCB is pretty quick on restocking things , join the wait list for a email when they are back in stock

Mike


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## Chuck D. Bones (Feb 4, 2020)

I use this one and it has not lied to me yet. Measures hFE accurately, leakage, Vbe. It doesn't give Vp or Idss for JFETs, but it does find an operating point in the linear region. It's good for a quick check and if I need more detailed info, I use a curve tracer. When I compare the test data from the Chinese tester and the curve tracer, they agree. Also measures inductance, capacitance & resistance.


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## mywmyw (Feb 5, 2020)

Mourguitars said:


> Mr PedalPCB is pretty quick on restocking things , join the wait list for a email when they are back in stock
> 
> Mike



I been on it for some time


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## Crookedtooth (Apr 28, 2020)

Chuck D. Bones said:


> I use this one and it has not lied to me yet. Measures hFE accurately, leakage, Vbe. It doesn't give Vp or Idss for JFETs, but it does find an operating point in the linear region. It's good for a quick check and if I need more detailed info, I use a curve tracer. When I compare the test data from the Chinese tester and the curve tracer, they agree. Also measures inductance, capacitance & resistance.


Hiya! Sorry, but which tester are you referring to? Do you have a link perhaps? Thanks so much!


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## lcipher3 (Apr 28, 2020)

The link is under Chuck's "this one" text- the forum doesn't show links well
Or here:  https://www.ebay.com/itm/182678167951


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