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@ -63,11 +63,10 @@ the required symbols in the preprocessor to build for different board revisions.
This is going to be difficult for all but the most technically advanced. The board features all surface mounted components, with 4 QFNs, a few SOT-363s and tightly spaced 0603 passives. Unless you're skilled with stencils and reflow, you will find it challenging.
The state of the supply chain makes it even more difficult to source some of the parts now, so the design of the kit will probably change to include widely available alternates. For instance, the LDFPUR (3x3mm) will be replaced by LDFPVR (2x2mm) which is available but also more difficult to solder. The AP63203 will probably be replaced by an AP3211 which was the original buck I used years ago (it just needs some extra filtering at its input). Also, a custom GreenPAK IC may be added to consolidate some functions and provide a hardware-based secondary watchdog. There is in fact a regulatory requirement that AIS transmitters have a hardware-based mechanism to prevent them from getting stuck in carrier transmit mode due to software lock-up and a GreenPAK is perfect for that.
The state of the supply chain makes it even more difficult to source some of the parts now, so the design of the kit will probably change to include widely available alternates. For instance, the LDFPUR (3x3mm) will be replaced by LDFPVR (2x2mm) which is available but also more difficult to solder. The AP63203 will probably be replaced by an AP3211 which was the original buck I used years ago (it just needs some extra filtering at its input).
With the above changes, and after being able to secure a quantity of Silabs ICs from a spot market in Shenzhen, it looks like the kit will become a reality in Q2. It will include a 98% finished PCBA as well as the VHF antenna, enclosure and sealing components. The board will be programmed, tested and calibrated, and the antenna will be perfectly matched.
*April 24 UPDATE*: Unfortunately, the state of the supply chain is getting worse, and at this point I have to stop working on MAIANA™ to rescue my other project. I will try to respond to discussions and issues, but I cannot build kits and it doesn't look like I'll be able to do this until after the boating season this year.
There is, however, one caveat: <b>I cannot legally ship this as a transponder yet</b>. The workaround is to bill it as an AIS+GPS receiver. To turn it into a transponder, you will have to <b>procure and install [inductor L4](https://github.com/peterantypas/ais_transponder/blob/master/latest/CAD/Board-10.0/transponder-10.0.1-schematic.pdf) on the PCBA yourself</b> (see page 5 of the schematic). Without this part, the circuit is physically incapable of transmitting. Soldering this should be easy as it is an 0805 package and the pads will already have solder paste from the original SMT and test process. The inductor is a Taiyo Yuden BRC2012T2R2MD and it's widely available at both DigiKey and Mouser. It is quite cheap, so your main cost will be shipping.
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