Is there a practical (real world) circuit out there that would require using an NPN transistor like that?

The Japanise used a "special" design BJT for audio muting circuit.
http://www.electroschematics.com/wp...1/Muting-Transistor-Application-Schematic.jpg
See the example:
http://pdf.datasheetcatalog.com/datasheet/toshiba/978.pdf
Or 2SC3326
And notice high reverse HFE and high Vebo voltage. They almost design full symmetrical BJT.

And here you find other untypical examples of using a BJT.
http://www.armory.com/~rstevew/Public/SoundSynth/Noise/PinkNoise/project11.htm
http://jlnlabs.online.fr/cnr/negosc.htm

 

But notice how those numbers don't match your sim results for the normal orientation.

If BF = 100, then to get a collector voltage of 852 mV the base voltage would have to be 810 mV.

If Vbe = 0.7V, then to get a collector voltage of 852 mV the BF would need to be 27.

Naturally the result did not coincide with the simulation. This is an approximate calculation. If I took the number 0.8B, not 0.7V, the result would be more accurate. I showed only a tendency. But I made the calculation as a schoolboy. Schoolboys are recommended to use for base-emitter voltage 0.7V.

 

Never heard of that rule before - that one junction will drop more forward voltage than the other. I've seen here people using Sim's to determine. Well, sitting at my workbench I just grabbed a 2N4403 and my meter. Here's the results of MY PARTICULAR TRANSISTOR CHOICE: (see the image below)

[edit]
2N3604 reads [EB 0.633] [BC 0.637]
2N3906 reads [EB 0.638] [BC 0.635]

NPN reads higher on the BC junction.
PNP reads higher on the EB junction.

{no new images}

 

Average of some BC547B (ON Semiconductor) forward voltages at 23°C:
BE: 711 mV
BC: 706 mV

 

Naturally the result did not coincide with the simulation. This is an approximate calculation. If I took the number 0.8B, not 0.7V, the result would be more accurate. I showed only a tendency. But I made the calculation as a schoolboy. Schoolboys are recommended to use for base-emitter voltage 0.7V.View attachment 126895

Oh, I thought you were saying that those were the actual model parameters.

 

PNP or NPN does not matter...The BE junction is always higher

 

PNP or NPN does not matter.

OK, maybe I did something wrong in my testing.

 

OK, maybe I did something wrong in my testing.

Yes. You did.

 

The Japanise used a "special" design BJT for audio muting circuit.
http://www.electroschematics.com/wp...1/Muting-Transistor-Application-Schematic.jpg
See the example:
http://pdf.datasheetcatalog.com/datasheet/toshiba/978.pdf
Or 2SC3326
And notice high reverse HFE and high Vebo voltage. They almost design full symmetrical BJT.

What's so special. It's just a NPN used specially for switching and muting.
You cooked up a symbol to make it look special.

 

Found the way, I think. To reliably pick out the C.B. and E.B.
I have a Handy dandy Heathkit Capacitor checker IT-28. Got it on Ebay for $29
It tests for 2 microamps leakage in capacitors up to 600 volts.
I use it to test the reverse breakdown voltage of the two junctions.
From my testing and looking at many transistor specifications the Emitter Collector
breakdown voltage is always at least twice as high as the Emitter Base.

 

This will work nearly all the time. Of course, most people don't have a suitable meter to do the test and it would not work on some specialty transistors that are designed not to have this characteristic -- but you probably won't ever run into any of them and there will always be some oddball transistors that nearly any means of distinguishing emitter from collector could be fool by.

The reverse breakdown voltage on the emitter-base junction is low enough that a pretty simple circuit could be put together to test which one breaks down and which one doesn't while limiting the current to a low enough value to prevent damage.