The unit over the last few weeks has performed great, i upgraded the battery to a 2250mah (original is about 1400 i think) and the controller seems to last over 2 - 3 days before warning the battery is low (about 3 hours of constant use, so by commiting to this circuit inside your PDA it mean treat your PDA as a TV remote, very little use). Unfortunately the circuit does run all the time, not sure when the PDA is sleeping (havent tested the drain across the circuit in that state). However, i plan to build a charging station on the wall so i can simply drop the PDA into it over night to charge. If you were to do this project then i strongly recommend upgraded the standard battery in a PDA to the best you can get. Look on ebay, cheapest and without a doubt the most mah you can get.
Ive found about 90% of the time the PDA with this circuit working well. The problem is the actual receiver (RF to IR) with two IR facing the cinema set. Although the distance is good (about 5m) the angle isnt of these IR LEDs so im either gonna redo the receiver and install 6 IR LEDS at slight angles or buy 2 wide angle LEDs as distance isnt the issue for me.
Using an SD card type size of this circuit isnt possible due to the transmitter chip being standard size. The hardest part of this project was actually fitting it into the PDA. The 3850 has tonnes of room inside around the SD card (especially in height which is what you need for the chip).
My wife to be very soon, has commented on the PDA as good thing to replace our 5 controllers but it needs a little tweaking to get it response each time you press the button (thats the 10% sometimes it doesnt respond and due to the IR transmitter not having enough angle or IR LEDs.)
One thing i did forget to mention when installing inside the PDA, the IR Reciever that sits behind the IR port of the PDA and using tin foil to reflect the IR signal back into it needs to fit over only the IR Transmitter of the PDA NOT the IR Receiver of the PDA. Usually the IR of the PDA is a transceiver, i.e. it'll be 1 component with two IR LEDs, one to transmit the other to receive. If your not sure which is which, then get a digital camera, view through the LCD of the camera the IR transceiver of the PDA (of course the PDA casing will have to be removed for this) and transmit a TV command, you then should see which of the IR is transmitting. IF you cover both IRs of the transceiver then you wont be able to learn IR commands from the remotes because its blocked!
