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The RF Switch should be changed for next rev. At the moment it complicates the system with a stupid inverter because it's layout is the opposite of what we want. Skyworks has a nice alternative chip which can be found in the parts selection.

I'd suggest using a different LNA for the next rev. The outer circuitry is certainly a little more complicated, but we actually have data for it in the 70cm band which we can only extrapolate from the MACOM chip. Alternative is in the Parts Selection of the LGR.

The battery charging configuration pins are wired wrong. As they are right now, the configuration doesn't allow for battery charging. There is also no timeout safety feature nor is the proper charge source selected nor is the proper usb current selected. Essentially this configuration is the exact opposite of what we want. The following needs to happen:

!TE needs to be tied LOW
SEL needs to be tied LOW
CE needs to be tied HIGH
PROG2 needs to be tied HIGH

The only solution right now is cutting the traces for these connections and mod wiring them as specified above. This needs to be rectified in V2 of the board.

The external oscillator has a footprint for a 32kHz clock. Thankfully, we were able to find a 32MHz that was just slightly larger than that footprint so we were still able to use it. However the footprint needs to be changed to match the 32MHz crystal.

Package for board layout is not precise enough. Looks like crap and needs to be revised before we do board layout.

No pull-down on the PA enable line so it's floating. It's mod wired on the current rev, but this needs to be fixed for the next one.

... not 3.3V. That way the LED still indicates charge status even if the board switch is off.

Feeding the clock output from the transceiver to the MCU, but then having to poke the transceiver over SPI first to get the right clock to feed the PLL is just silly. Adding an extra oscillator wont be that much more complicated in hardware and will greatly simplify firmware.

We couldn't find the kingbrite tri-color LEDs that we wanted to use so we had to use a similar tri-color LED. However its footprint is different from the kingbrite one. We need to change it in V2 of the board.

On the next rev of the dev board. They're currently #2 and no one has hardware sized correctly to stick through them.

RF trace lines need to be around 109 mils, but we can only fit about 55 mils and we only used 30 mils for this board rev. When we move to a multi-layered board this issue can be fixed though.