"Jasen Betts" wrote to "Thom Kouwenhoven" (06 Jan 03  18:22:42)
 --- on the topic of "I/F"

 JB> Hi Thom.

 JB> 05-Jan-03 18:21:43, Thom Kouwenhoven wrote to ROBERT SAYRE


 TK> Hi there ROBERT

 TK> On 04 Jan 03 15:45 you wrote something about *I/F*...

 TK>>> Exactly....only "mute"...but that is so
strange...there is no
 TK>>> form of powersupply connected to the collector at all...and yet
 TK>>> it works :-)

 RS>> The "power" is the audio (AC) coupled through the capacitor.

 TK> And how does it work during the negative phases ??

 JB> Transistors work backwards!
 JB> You can swap C and E and they still work (but at reduced gain).

That's true but, as you mention, the gain is often about 100 times less.
Speaking of gain, I once measured an oddball switching transistor type
in which the gain was the same on either terminal. Worse still the B-E
breakdown voltage was similar to B-C. The only way I could identify the
collector was by the lower capacitance and lower B-C forward voltage. I
think it came out of an IBM370 surplus board. Those were populated with
forests of metal case 2N1000 series.

 Mike
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