The next task was to put the receiver in a box. As I wanted to make the receiver powered by 12V I needed room for a DC to DC converter and possibly some external filtering (to get rid of 198kHz droitwich for instance). For the same reason I wanted a screened metal box
Searching the mouser diecast box lists I could not find on just big enough but i did find one that would do, so i ordered it. I did have to 3D print some 3mm threaded spacers of appropriate lengths as the 2 boards were at different heights above the bottom of the box.
Initially I used an LT1084 Low volt drop regulator to regulate the incoming 12V down to 5V directly to supply the FPGA board and hence the Receiver board, but it got hot, not good for reliability. So I considered using just a chinese DC/DC converter to drop the 12V supply directly down to 5V. However having had these boards fail in the past and put the full input voltage at the output I devised an alternative. I used the Chinese LM2596 DC/DC converter set to produce 8V output then used an LT1084 Low volt drop regulator to produce the 5V. This way if the DC/DC failed and produced full output the LDO regulator would protect the board. This was the method eventually used.
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