Super Simple Oscillator (Transistor Arrays?)

Ive been thinking about transistor arrays and the super simple oscillator.

Known voltages that can cause Avalanche:

Im curious if there is a predictable way to determine what voltage would be required to breakdown.
The emitter-base and the collector-base min voltages for breakdown dont seem to directly indicate the observed minimum voltages needed.

I could of course be way off base and even have selected the wrong dang type of transistor here.


You’d want the 2082A, wouldn’t you? Common collector? (Oh, right, that’s what you linked. I was looking at what was written on the datasheet excerpt.)

Wong’s circuit (and Sam’s) has an LED between collector and ground, you’d have to forego that with an array. Or just have one LED for all 7 transistors.

My guess, and it is only a guess, is that the number you want is the emitter-base breakdown voltage plus (if an LED is present) the LED forward voltage, but the SS9018 and 2N2904 datasheets, at least, don’t quote a typical or max breakdown voltage, only a minimum, and probably the actual value varies quite a lot. But the 2081 datasheet shows 7 V typical, which if my guess is right is encouraging. On the other hand the 2N3904 datasheet shows 6 V min, only 1 V above the SS9018 min, and we know it needs about 4 V more according to Wong, so <shrug>.


Good idea. Looking forward to see how it develops