uBitx under construction. Extra signal processing arduino, touchscreen, 24V step up supply for the PA (40W out ssb 80m, 10W out ssb 10m), internal Raspberry Pi (waiting for Pi3 to arrive), space for internal LiPo battery approx 2500mAh at 14.8V. I should be able to squeeze SDR receiver in there, and the Pi will be able to control the transceiver, generate audio for datamodes etc. There will be USB and HDMI ports on the back and maybe the front too, for a wireless nano adapter and keyboard/mouse etc.

Power supply section of the uBitx the vertical board is a 15V supply for the uBitx mainboard and for charging the internal battery. The square board with the heatsinks is the 24V supply for the PA. The small one at the front is for the display. The arduinos run from a linear 5V regulated supply on the Raduino board, due to psu noise being too high for the audio processing on the signal board. These supplies are mounted on a centrepiece of copper clad board, which shields the RF receiver sections from the switching supplies and the Raspberry Pi. Initially, as expected, I experienced some interference from the switchers and computer, however I was able to reduce the interfering signals to surprisingly low levels by including large RF chokes at the power inputs of each module, preventing stray RF hash from going back into the main power supply line.

Some of the mods from left to right: SWR bridge, with forward and reverse voltage out trimpots. Anti-hiss LM386 mod. Variable filter bandwidth mod. It varies from about 1kHz wide to 3kHz wide. SWR protect and front panel drive control mod. RX to TX RF transient mod. PA mods: Upgraded inductors in PA+V line with thicker wire. Provided stouter PA +V feed with more wire. Audio mods: Replace 0.1uF caps in RX and TX audio amplifier with 22uF. Replace LM386 output capacitor with 330uF. 

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