Is this feasible? searching for it seems to keep finding stuff related to Gunn diodes, tunnel diodes and so forth.
Consider:
If a suitable voltage is applied, then C1 will begin to charge through R1, D2 will have an insufficient voltage (less than around 0.6v) across it so will not conduct, no current will flow through, effectively and open circuit - all the while though, that voltage is rising.
As C1 charges, the voltage across D2 will rise until it reaches around 0.6v or so, then it will begin to conduct, at which point it begins to act as a discharge path for C1.
If C1 discharges to a sufficiently low voltage again, the voltage across D2 will fall below 0.6v and it will cease to conduct, so cease to provide a discharge path for C1.
So I'd expect C1 to again begin charging again and the entire cycle repeat itself.
On paper then it seems to offer the prospect of oscillation given suitable values for R and C.
Is this feasible? if not why not?
I'm not saying its useful, I'm sure it would have all kinds of drawbacks etc. but would it, could it, actually oscillate?
(I was just fiddling around with this (I used an LED that was lying around for the diode) and as I slowly increased the applied voltage, I did see what looked like huge instability and lots of high frequency noise on the scope (voltage across the diode) at certain points, but it was odd, not sure if it was oscillation or just noise due to other factors).
Consider:
If a suitable voltage is applied, then C1 will begin to charge through R1, D2 will have an insufficient voltage (less than around 0.6v) across it so will not conduct, no current will flow through, effectively and open circuit - all the while though, that voltage is rising.
As C1 charges, the voltage across D2 will rise until it reaches around 0.6v or so, then it will begin to conduct, at which point it begins to act as a discharge path for C1.
If C1 discharges to a sufficiently low voltage again, the voltage across D2 will fall below 0.6v and it will cease to conduct, so cease to provide a discharge path for C1.
So I'd expect C1 to again begin charging again and the entire cycle repeat itself.
On paper then it seems to offer the prospect of oscillation given suitable values for R and C.
Is this feasible? if not why not?
I'm not saying its useful, I'm sure it would have all kinds of drawbacks etc. but would it, could it, actually oscillate?
(I was just fiddling around with this (I used an LED that was lying around for the diode) and as I slowly increased the applied voltage, I did see what looked like huge instability and lots of high frequency noise on the scope (voltage across the diode) at certain points, but it was odd, not sure if it was oscillation or just noise due to other factors).
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