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transistor tester?

lcipher3

Member
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.
 

lcipher3

Member

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
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



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

Well-known member
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
 

lcipher3

Member
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 :oops:

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

lcipher3

Member
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)
 

Mourguitars

Well-known member

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
 

Mourguitars

Well-known member
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
 

lcipher3

Member
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?
 

Mourguitars

Well-known member
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
 

lcipher3

Member
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.
 

PedalPCB

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

The DCA75 reads them accurately.
 
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