Transistor E2AFAA 89 08 274, need explaination please

I think this is a TO type Transistor but that is all I know

I have two of them I need to replace, but I don't know what to buy

E2AFAA 89 08 274
E2AFAA H1 23 274

I'm guessing that the E2AFAA and 274 are the main numbers to take into consideration but I can't find any transistors on line to buy are near these numbers.

Thank you for your help

Doing a quick look, I could not cross those numbers either. Is this used in a power supply (DC switch/rectifier) or an audio amplifier?

That is not commercial wide offered part its maybe manufactured specially for some need of some manufacturer. Such things dont exist in datasheets databases.

ge said:

Doing a quick look, I could not cross those numbers either. Is this used in a power supply (DC switch/rectifier) or an audio amplifier?

Click to expand...

It's from a Lincoln Mark VII trip computer.

Is there a way I can test a working one to find out what the specs of a new one should be? I am a complete newbie - can I ascertain the info I need using a multimeter?


Thank you!!

I suggest you may take some pictures of the PCB (component side/solder side), attach them here and based on the photos to decide if that’s a bipolar transistor or maybe some IC voltage regulator circuit.
Also, as a second suggestion, you should try to replace first the electrolytic capacitors. More details to come if we have the PCB photos…

Please let me know any info you can provide based on the pics.

Thanks!

What are the characteristics/ratings of this type of transistor and how can I test to find the ratings of this one?

Thank you

Try to take more close-up photos (with macro setting on) of the PCB alone in that area, to reveal connection details and no other objects in-between.

mister_rf said:

Try to take more close-up photos (with macro setting on) of the PCB alone in that area, to reveal connection details and no other objects in-between.

Click to expand...

Let's assume I have no circuit board anymore. What detective work can I do with just the transistor?

Is there such a thing as a TO-274 transistor?

That’s a bipolar transistors either a PNP or NPN configuration.
Bipolar transistors has 3 pins: emitter(E), base (B) and collector (C) which is usually connected to the casing for most power transistors. A simple multimeter test is based on the theory that a transistor is like two diodes connected together. Most of the multimeters are equipped with two separate continuity check functions: resistance and “diode check’’. Normally you may use the designated “diode check” function and the meter will display the actual voltage of the junctions.

Transistor pinout from the left to the right: Base on wire 1, Collector on wire 2 and Emitter on wire 3
First testing the Collector -Emitter junction.

Connect the negative probe (Black) to Emitter and the positive probe (Red) to the Collector
Meter reading: “OL” (high resistance)
Connect the negative probe (Black) to Collector and the positive probe (Red) to the Emitter
meter: “OL” (high resistance)
This indicates a possible working transistor
------------------------------------
Following tests to determine the correct NPN/PNP configuration.

The transistor is a PNP for the results:
a)Connect the positive probe (Red) to Emitter and the negative probe (Black) to the Base
E and B forward connection, meter reading: 0.600V up to 0.800V
b)Reverse situation, connect the negative probe (Black) to Emitter and the positive probe (Red) to the Base
This is the E and B reverse connection,
-meter reading: “OL” .- standard transistor
-meter reading: 1.2V up to 1.9V Darlington transistor

c)Connect the positive probe (Red) to Collector and the negative probe (Black) to the Base
C and B forward connection, meter reading: 0.600V up to 0.800V
d)Reverse situation connect the negative probe (Black) to Collector and the positive probe (Red) to the Base
This is the C and B reverse connection, meter reading: “OL” .
----------------------------------------
The transistor is a NPN for the following results:
a)Connect the positive probe (Red) to Emitter and the negative probe (Black) to the Base
E and B reverse connection,
-meter reading: “OL” = standard transistor
-meter reading: 1.2V up to 1.9V = Darlington transistor

b)Reverse situation connect the negative probe (Black) to Emitter and the positive probe (Red) to the Base
This is the E and B forward connection, meter reading: 0.600V up to 0.800V
c)Connect the positive probe (Red) to Collector and the negative probe (Black) to the Base
C and B reverse connection, meter reading: “OL”
d)Reverse situation connect the negative probe (Black) to Collector and the positive probe (Red) to the Base
This is the C and B forward connection, meter reading: 0.600V up to 0.800V.

If we were to measure continuity in any more than two or any less than two of the six test lead combinations, we would immediately know that the transistor was defective.

Thank you! Based on those test one I believe they are PNP standard transistors.

The working one yielded

.585V on PNP test A
.586V on PNP test B

The non working one yielded
0V on PNP test A
.310v on PNP test B

So now that I know it is a PNP standard transistor, how do I know what model# to replace it with?

Try to find any bipolar PNP transistor, Ic= 7A-15A, Uce>50V see for example:
BD912
BDW94C
BD708
MJE2955T
MJE15029
MJF2955G
TIP102
TIP107

2N6042G
2N6040G
2N6490G
2N6388,
2N6668,
2N6491

What do you think of TIP42 ? It is the only thing I could find at the local store

TIP42G PNP Transistors - RadioShack.com

---------- Post added at 23:16 ---------- Previous post was at 22:00 ----------

I bought TIP42 and TIP120 which would you use? (knowing nothing about the circuit)

TIP42 = PNP type and TIP120 =NPN type, :-D so you need to use TIP42. (This is a fairly low gain transistor, I hope here a lower current gain may be acceptable.)