Relaxation Oscillators - Solid-state Devices and Analog Circuits - Day 6, part 10

[@basicaodaeletronica]

AS melhores explicações de como funcionam osciladores

[@eytansuchard8640]

In modern days, low frequency for power switching, e.g. 8 K Hz, can use a Thyristor. Someone posted a circuit with BT151 with circuit voltage of 5 volts.

[@mikesradiorepair]

They still make normal (non programable) UJT's. I have a 50 or so 2N4870 which is still made. For the life of me I can't remember what I stock them for but I would have bought them for inventory if they were in something I work on.

[@Vocademy-Electronics-Tech]

Wikipedia, the most reliable source of information on the internet (hoc est taurum stercore), implies they are no longer manufactured. I found them on Amazon but they could have been old stock. A quick search didn't find anything that clearly said they were still manufactured. Thanks for the info.

[@mikesradiorepair]

@@Vocademy-Electronics-Tech DigiKey and Newark show them as still active. Newark shows the manufacturer as Multicomp Pro.

[@fano72]

Maybe a cool pwm audio oscillator, we should try that.

[@gregwmanning]

Thanks for video I got 10.34Hz not 1kHz using formula provided earlier and values provided later. I may have miss-applied the formula? f = 1 / (2 x Ln(3) x 22u x 2k)

[@fano72]

Same here. If you use 4.7k with 220nF, you get 440 Hz which is realistic.

[@david_pilling]

Could use an SCR/thyristor instead of Unijunction - same semiconductor layers, different connection. If you really want something that is officially still manufactured.

[@odysseus9941]

😄Can I run this oscillator with AC or DC supply voltage?

[@Vocademy-Electronics-Tech]

Like most circuits, it requires a DC power supply.

[@aziaufa418]

I just dont understand at all how this works. Every single simulation behave differently (tinkercad, ltspice, proteus)