Adding LED's to show actual fault cause to a circuit question

[Chris Wilson]

I have a working version of this circuit I built some time ago. Instead of the center tapped transformer I use two 50V, 40 or so Amp computer server switch mode power supplies in series, for a fully regulated 100V to the Class D FET's, and a separate linear regulated 12V DC supply for the rest of the circuitry.

I have shown the state of the gates used for over current protection to the PA FET's, excess reflected power from the SWR bridge, and loss of the 272kHz input signal with the amplifier working normally, on an abridged schematic showing the amp in the form I am using it. I also attach the originator's build documentation, but note I deleted some early circuitry as I already had a suitable (Kenwood TS-590 1mW exciter at 136kHz), and a pre amp and frequency doubler to feed my abridged circuit at 272kHz.

As it stands a single LED shows if the circuit has gone into fault mode, due to high reflected power, too much PA current, or no input signal. I am rebuilding the amp mechanically to give much easier access for maintenance and repair, and would like 3 separate LED's to show just which of these three faults tripped the amp.

IC6 has a spare trio of input pins and an output pin, and IC1B has 3 dual inputs unused.

Can anyone much cleverer than I see a way to have 3 separate LED's showing just which of the three possible fault states tripped the amp please?


Finally, am I right in thinking that diode D3 is there to stop voltages above about 12V reaching the gate pin 13 of IC1B, if the SWR bridge got really excited with reflected power? If not, what is its function?

Thanks.

[strawberry]

How about mosfet driver with SD function like IR2184...
simplest way is to use single microcontroller to hook all LED's and delay need, or drive LED with emiter folover from sensor directly
D3 no doubt.