by Sangoma » Sun Jul 26, 2020 4:30 pm
This is now set to be my next major project.
No doubt it will be a long one, as it will be built in basic form first, and completed on the go, ie manual band selection with automatic to follow, simple auto tuner, and better one with memories.
Sequencing and control will be logic, but protection circuits will be linear.
I have decided not to make it too small, it will be about 250W X 350D X 120H.
This will allow fairly quiet cooling for 400W on a 50% duty cycle, and 600W capability on a 30% duty cycle, which means it should handle 600W SSB all day
I think I will end up making a main board to handle the protection and power supply, a processor board to handle the sequencing, band selection and rig control, and of course another board for the tuner. The logic board and the tuner only need to communicate band data, which I will do with Yaesu 4 bit BCD
It will be fully automated with the FT-991, FT-817, X5105, IC-703 and the IC-7300.
It will have 3 antenna ports, 2 HF and one 6m/4m, though as yet I am not certain of the amplifiers performance on 4m, may be limited to 300W.
It will NOT have full break in for CW, absolutely no use to me
Two protection circuits; SWR, high input power, over current will cut the main power requiring a power cycle to reset, over temperature will cut all low voltage supply except the fans, meaning it will be re-enabled when the temperature comes down, and can't be reset.
I have started designing another tuner board, which will be stackable with the LPF board (bought as a kit, capacitors I need are on order and won't be here for months maybe, can't wait that long
)
It is a lot more complex than the 1.2kW amps, so at the moment there seems a lot to do
This is now set to be my next major project.
No doubt it will be a long one, as it will be built in basic form first, and completed on the go, ie manual band selection with automatic to follow, simple auto tuner, and better one with memories.
Sequencing and control will be logic, but protection circuits will be linear.
I have decided not to make it too small, it will be about 250W X 350D X 120H.
This will allow fairly quiet cooling for 400W on a 50% duty cycle, and 600W capability on a 30% duty cycle, which means it should handle 600W SSB all day :)
I think I will end up making a main board to handle the protection and power supply, a processor board to handle the sequencing, band selection and rig control, and of course another board for the tuner. The logic board and the tuner only need to communicate band data, which I will do with Yaesu 4 bit BCD
It will be fully automated with the FT-991, FT-817, X5105, IC-703 and the IC-7300.
It will have 3 antenna ports, 2 HF and one 6m/4m, though as yet I am not certain of the amplifiers performance on 4m, may be limited to 300W.
It will NOT have full break in for CW, absolutely no use to me :)
Two protection circuits; SWR, high input power, over current will cut the main power requiring a power cycle to reset, over temperature will cut all low voltage supply except the fans, meaning it will be re-enabled when the temperature comes down, and can't be reset.
I have started designing another tuner board, which will be stackable with the LPF board (bought as a kit, capacitors I need are on order and won't be here for months maybe, can't wait that long :) )
It is a lot more complex than the 1.2kW amps, so at the moment there seems a lot to do :)