BD139-16 & BD140-16? Anyone use these transistors?

[lineup]

.
here a close up

The pair, is a 'matched complementary' pair BD139 BD140
.. with my test figures on a paper attached with piece of wire.

Also can see some simple home made heatsinks
I use sometimes just in case.
I have bigger heatsinks for TO-126 TO-220 for 'hotter bias' applications, approaching temperture limit


Regards lineup

[lineup]

I still have a couple of those TO-3 big BUX39 left.
I bought 10 of them from a surplus sale, for almost nothing.
They are good for some heavier Currents non-Audio-amplifier things.

Those 2 caps are Polypropylene Axial:
marked: ERO KP1832, 200V=, 5%, 0.43uF

In upper right is a capture from A slaughter of old Transformator.
Enamelled copper wire is good for many things ....
in my little corner of my room company:
LIneup Audio Lab >>>> .. like 4 square meter. ( 2m x 2m )

But dont you go fool your selves, too much
- plenty of small goodies is too be found inside that little limited space of my life

Image #3 - my last for today.

[peranders]

Originally posted by grhughes
I've never used SMT devices. I guess they have to lay flat??

That's the whole idea behind surface mounted parts. Cooling SMT devices requires some considerations about the pcb.

[gaetan8888]

Originally posted by jacco vermeulen
Back in the old days you had to open a semiconductor book to look at a datasheet, instead of clicking a pdf.
Of course, the semiconductor data book comes free if you've got a relative employed at the Philips NatLab in Eindhoven.
Free online datasheets often are abbreviated versions, sometimes saves you 10 to 14 pages.

A bunch of BD139/140s in parallel make a fantastic class A headphone amp output stage.
Philips versions are much nicer, Cob of 5.7pF, downside that the power they handle is 2/3d of the different die version.

Hello

Where did you find the Cob spec of the BD139 ?

I've never seen it in all versions of data sheets that I have.

Thank

Bye

Gaetan

[lordearl]

Do these ones look like genuine Philips units?

[sbrook]

They don't look like mine ... which were manufacted by Philips about 25 - 30 years ago ...

The ones I have have the printing of the type number on the bottom row closest to the pins ... not the next row up, like these. The three moulding dots are located close to the through hole, the edge is under 1 mm away, unlike these that have the moulding dots almost in the upper corners of the body.

[terranigma]

Originally Posted by x-pro

On top of what already was written by jacco, I would add that it is possible to check the capacitances of the device if you have a capacitance meter. If my memory serves me right, Philips BD140 would have B-C capacitance about 50-60pF at 0V, and ST etc. - about 100-120 pF. In any case the capacitances on BC640 and Philips BD140 (and their NPN complements BC639/BD139) are near identical.

x-pro

I just measured CoB capacitance of some BD's that I have at 0V for comparison.

ST BD139 50pF
No brand BD139 (PH402) 102pF
Philips BD139 30pF

Philips BD137 32pF
Harris BD137 22pF
No Brand (PH99) BD137 52pF

Philips BD140 52pF
Harris BD140 35pF

I find almost nothing about those Harris devices at internet. I look forward to find some info about their specs, especially Ft.

[tinitus]

no mention of original Motorola ?

I have a few with greyish house and gold legs
but they have been pulled from burned amp many years ago, so I will need to check them

[tinitus]

UPS!
I had not noticed this is a reopened older thread

but whatever, I measured my old Motorola BD139/140
not that I know much about how, but with diode function on my multimeter, I read 900...something
from one leg to other two, on all the shown devices

so I guess they are all ok ?

[terranigma]

You must have a capacitance meter which able to measure in picofarads. You have to measure 2nd leg (Collector) and 3rd leg (Base) with capacitance meter for comparison.

If you want to know your transistors are working or not, just measure their HfE using a suitable multimeter. Many multimeters contain this feature rather than capacitance measurement.