Recent content by zsolt2

Thank for all of your help!

My calculation shows 16.16 which is a good estimation (although it could be a coincidence and the equation I used wrong) How did you calculate the input impedance of the second stage? The only equation I know to get it is Rb||(hie+Roc(1+hfe)) Where Rb=8.2k||18k and Roc=27||8 But hie is not given...

There is a data sheet given to the assignment that's where I got hie and hfe

Sorry I put the wrong formula in the equations box I used Gv=-Rc/(Re+re) Where re is hie/hfe in this case 5500/370 Is that sounding better?

The 8.2 and18 k resistors are forming a pot divider: 12x 18000/(8200+18000)=8.244V at Vb Ther is about 1.4V drop in the Darlington pair, so volt across 27ohm resistor 8.244-1.4=6.84V So the output voltage is 12-6.84=5.16 In the simulation it comes out to 6.12V But I don't know how does it help me?

No, I can't use any other model

Thanks for your answer. I know what you mean by that, but the data sheet I was given to the assignment doesn't contain the value oh hoe, nor the hie of the BFY51 transistor (the second one, hie2), so I am unable to calculate the load on the first stage as the hie of the combine transistors is...

Oh and the gain of the common emitter stage in the PSpice circuit is 15

Thanks for your answer. I remembered that I forget to add re to the equation which is hie/hfe. (a data sheet was given to this assessment). For this transistor hie=5.5kohm and hfe=370 so re= 5500/370=14.86 The gain of the circuit is then 1000/(47+14.86)=16.16 So the output signal of the first...

Homework Statement Hi all. I need a bit help with the following. Estimate the power developed in the 8 Ω speaker of the circuit of FIGURE 2 for a 1 kHz sinusoidal input signal of 100 mV peak. All capacitors may be assumed to act as a short circuit at the frequency of operation. Compare your...

Thank you Jim!

Hi all. I need some help with the circuit attached. For the diode to conduct, at point X the voltage must be 0.6V minimum. There is an equation to find the minimum required voltage input, Vin to give 0.6V at X. What I don't understand is the right hand side of the equation; why is it...

Hi. Yes I think I have solved it P.f.=0.89 I= 11.24 If I am right Thank you

Homework Statement A star-connected, three-phase synchronous induction motor takes a current of 10 amps from a 415 volt supply at unity power factor when supplying a steady load. If the synchronous reactance is 5 ohms/phase and the resistance is negligible, draw the phasor diagram and...

Ok thank you very much for the help!