I need to repair this RF amplifier, although it never work, it's cheap one, and you don't have any schematic at all, and take care for heat dissipation, you need to buy MRF300An and MRF300BN mosfets, which I did but when everything connected, and board need two power supply one for drain and one for gate side, so I put voltage regulator on power supply for drain side, which need 53V, and downgrade voltage around 10.5V for gate side, but when is everything connected I don't have any current flowing!!!???,
I Can't regulated voltage with trimmer more than 2.2V on both side, and on amplifier board says that bias voltage need to be 2.7V or 0.3A. When I turn voltage around 2.3V on both side, than starts sudden drops in voltage on power supply, and current jumps around, but I regulated (blocked) with power supply max of 0.5A to let on amplifier board, just because that mosfets don't burn, so breaking point for both mosfets are around 2.3V, but again both side AN and BN are connected, you can't regulated with trimmer slowly current, although this trimmer are for fine step by step regulation.
Strange is also that I can continuity (diode mode) from ground to gate side, but I don't have continuity from ground to drain side.
Mosfets are new, and like to determine where is issue if someone can help
I Can't regulated voltage with trimmer more than 2.2V on both side, and on amplifier board says that bias voltage need to be 2.7V or 0.3A. When I turn voltage around 2.3V on both side, than starts sudden drops in voltage on power supply, and current jumps around, but I regulated (blocked) with power supply max of 0.5A to let on amplifier board, just because that mosfets don't burn, so breaking point for both mosfets are around 2.3V, but again both side AN and BN are connected, you can't regulated with trimmer slowly current, although this trimmer are for fine step by step regulation.
Strange is also that I can continuity (diode mode) from ground to gate side, but I don't have continuity from ground to drain side.
Mosfets are new, and like to determine where is issue if someone can help