"Phil Allison" wrote in message
...

"Gareth Magennis"


I recently bought some TIP35C transistors from Farnell UK. Just before I
fitted one to an amplifier I thought I'd just check the pinouts.
Good job I did because instead of BCE they measured BEC.


** That is just not possible.

The middle leg is always the collector and metal tab used for heatsinking.

FFS - get an ohmmeter and verify that simple fact.

Seems your dopey microprocessor ( ie software) based POS has gone ape and
confused Collector with Emitter.



.... Phil




I did suspect my dopey checker, but even with a fresh battery it ALWAYS
reads EXACTLY the same,

which is: 3 of them measure BEC with an Hfe of 5, the other one BCE with an
Hfe of 20.
(All tabs connect to centre pin)

The replacements I finally got from Farnell with a different batch code
measure an Hfe between 40 and 70.


I know Hfe is kind of meaningless on these types of checker voltages, but
was still wondering why the checker would give a different pinout result
rather than fail the device.

I suspect all 4 of the "old" transistors are faulty, but still doesn't
explain how these managed to be sold to me by Farnell, or even got off the
production line without being checked.


Cheers,


Gareth.