Power Supply Completed.

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Well this is how the completed power supply turned out. For those wondering at the over-engineering. Yes, this power supply while very simple is completely over the top for a little Minima. The beauty of the Minima is that it serves as a platform for experimentation.

So I’ve build the supply with both + and -12 volt DC rails. Just in case I might want to play with split power supply audio amplifiers or similar. There is a +9v regulator that feeds from the +12 volt supply. Which in turn feeds to the +5 volt regulator on the logic board. So now the +5 regulator does not get so hot.

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The supply can also provide ~40 volts DC. Which may come in handy for getting higher power from a IRF510 linear. Perhaps…

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To the left is the Arduino Logic PCB mounted above the completed power supply. With the master power LED on the bleeder resistor winking out at us. “Yes I’m working and don’t poke your fingers in here!”.

To the right is the top view of the logic PCB mounted atop the power supply and the entire module bolted back onto the radio chassis.

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Finally another shot of the radio powered up. This time the photo is not as contrived as previous. She is running on her own internal power supply source.

It is interesting to note that this photo was taken with the “Raduino 0.4” sign-on message displayed on the LCD screen permanently. No trick photography nor hung I2C data bus. It just happens from time to time when everything is very stable and the shack has warmed up to a nice cosy constant temperature. As soon as you move the tuning knob it starts displaying the frequency. A quick glance at the source code and I’m convinced that this is normal behaviour. The current Raduino sketch does not display the frequency until there has been some sort of update.

Mostly though when people see the “Raduino 0.4” message forever it means that the I2C data bus is in a hardware fault condition which seems to hang the Arduino Wires Library.

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