flows for appreciably less than half of each cycle
Yes, if the input stays high, then the speaker burns up. Can you 100% guarantee theArduino I/O pin will always be low 100% of the time when not using the amp?
So as a simple "square wave" amplifier (or indeed digital switch) are there any problems with the above circuit?
QuoteAs I recall, Class C RF amps rely on the low-duty "ping" to stimulate the LC tank, and set it to oscillating.Right! low-duty "ping" or a spike like pulse. Most RADAR amplifiers operate as class C. A Low duty cycle packs all that power into a very narrow bandwidth, like a CW transmitter as well.
As I recall, Class C RF amps rely on the low-duty "ping" to stimulate the LC tank, and set it to oscillating.
Quoteflows for appreciably less than half of each cycleSo what is the class if current flows for half of each cycle, as here? As I recall, Class C RF amps rely on the low-duty "ping" to stimulate the LC tank, and set it to oscillating.
Very nice - but will it give Tone outputs that nice warm Tube sound?
Oof, 1/2 Amp through the transistor when input held high. Nice 2.5W glow worm.
Quote from: oric_dan on Apr 02, 2013, 11:38 pmOof, 1/2 Amp through the transistor when input held high. Nice 2.5W glow worm.Well, maybe you can show me the math on that? Vce measured at .5V in my test rig with that rascally little ole input held high. That's .25W where I live. And if you're real paranoid about it, decouple the DC with a cap on the input.
Just wondering though, why would you leave the input high? Do you not have control over that in your world? Interesting. Here in Canada microcontrollers do what you tell them to. Unusual, I know, but must be a Great White North thing.
5V/10ohms = 0.5 Amp.5V*5V/10ohms = 2.5 Watts.
Plus, it's much much worse if you're not providing enough base drive to saturate transistor.Worst case, 1.25 watts --> transistor=poof!
Read post #43.