[help!!!]

hi henry,

The T(t) is the instantaneous Torque of the motor with respect to time and its composed of the 'B' and 'J'
Torque, B component is due to the angular rotation and the J component is due to the acceleration of the motor, both with respect to time.

If the motor is at a steady angular velocity, ie: not accelerating the J component is zero.
So the Torque = B.

Regards

[parallel port not working]

hi pier,
If your PC's parallel port is not accepting commands, it maybe your operating system.

Are using Win XP?, if yes, then it will block access from your program to the port.

If required download from the web 'inpout32.dll' and place it in the Windows/System directory.

Also check your PC's port Bios settings at boot up, the parallel port has a number of optional settings.

[12v to 230 volts dc with voltage doubler circuit its possible?]

hi,
You say that you want to power a PC from the output?

This will mean, if you are using a standard 'desktop' PC it will have to be 230Vac at 50/60HZ.

Its possible to buy a +12Vdc to Mains invertor, rated at say 300Watts, that will drive a PC.

The circuits you have posted are for doubling, with a Vdc output.

[Question: Can computer burn your house down?]

hi,
I would recommend that if any electrical appliance can be switched OFF, it should be switched OFF, whenever, the premises where the equipment is located are unoccupied.

Obviously certain equipments have to be powered ON so that they can give a 24/7 service.

The important aspects of energy conservation and global warming should be remembered when operating equipment 24/7.

[Volt/Ammeter LCD panel into Powersupply]

hi bb,
The capacitor is C1.
J4/3 is the ground [0V] connection for the VM gnd.
J4/2 is measuring the voltage drop across R7, the psu current sense resistor.
J4/1 is measuring the  voltage output of the psu.
J3/1 is the Vsupply to the the VMeter.

The fact that C1 is drawn as a non -polar cap in the 'sketch' is just a quick way of drawing it,,, its a
polarised cap.

Hope this helps, if not re-ask.
Regards

[Feed back amplifiers]

hi,

Look thru the www.analog.com site, they have many application notes that you may find useful.

[help me read this circuit? please?]

hi quincy,

Its just another symbol for ground, 0V ref for the +/-Vcc supplies.

Does that help?

[PIC won't work with capacitors]

hi,
Look at  page 93 of the 16F62X datasheet.

Are you using a series or parallel cut crystal?  also note the possible requirement for a series resistor in one leg of the crystal.

Have you correctly configured the PIC using the _CONFIG, to suit your crystal?