The following is a 60 - 90W High Quality power amplifier. Circuit topology is about the same of the above mentioned amplifier, but the extremely IRFP9240 Rugged IRFP240 MOSFET devices and are used as the output pair, and well Renowned high voltage Motorola's transistors are employed in the preceding stages. The supply rails prudentially voltage was kept at the rather low value of + and - 40V. For those wishing to experiment, the supply voltage rails could be raised to + and - 50V maximum, allowing the amplifier to approach the 100W into 8 Ohm target
Rangkaian 60watt Amplifier Mosfet
Skema Rangkaian 60watt Amplifier Mosfet
Note:
* A small, U-shaped heatsink must be fitted to transistor Q6 & Q7.
* Mosfet Q8 & Q9 must be mounted on large heatsinks.
* Quiescent current can be measured by means of an Avo-meter wired in series to the positive supply rail and no input signal.
* Set the Trimmer R10 to its minimum resistance.
* Power-on the amplifier and adjust R10 to read a current drawing of about 120 - 130mA.
* Wait about 15 minutes, watch if the current is varying and readjust if necessary.
