Powernumpty

I believe 5.5mm OD 2.1mm ID

2.5mm ID is fairly common and will cause issues.

I keep a few adapters from universal power supplies to check and/or adapt.

Regards

Stu

I still think the mid-plate build is a good route for the AI. (if not in the original case)

Yellow for Kiwi+AI, Green for AI. Purple just to hold the lower 6x40x50mm plate on (holes all wrong for best heat transfer without distorting the plate here)

Red not used.

60mm Kapton tape over the purple holes (with screws) and entire length of the plate, 0.8/1mm fibre washers under the KiwiCape.

Only thing to watch for is the DC socket pins, might want to notch the plate there.

I just haven't worked out an inexpensive way to put that sort of plate in the proper case getting the heat out but not having to modify the shell. Obviously depending on the amount of material in contact it still needs some air movement but many times less than small heatsinks.

Plus I do believe there are noise gains to be had, don't have hard figures just gut feeling.

Stu

I shudder to see some of the things sold now. I forcibly get to test a new one very week or two as a close neighbour buys a budget item, kids break it then buy another, worse. The other side gets a new bit of computer kit to review on the same schedule. I've become like a wine taster now - "ah PC PSU, thick odour of Corsair with DC extensions, underlying LED strips and VDSL" - absolutely revolting!

I have found the MLA-30 didn't work powered from the BBG USB port here but I had assumed that was some failure of the design rather than no supply to the port (will have to go get one and check..) .

As the power injector for the MLA has a 5V-12V step up I didn't try again seeing that as a bit of an issue for HF. If you want to use it with the boost I'd split out the 5V before the Kiwi and try it there, the other advantage of doing it that way is some filtering between the MLA boost switcher and the RF side.

Personally I would use another Bias-T and feed a linear voltage to the MLA avoiding the boost, it would probably run from a 9V battery that way.

73 Stu

Why is it not good?

I know feeding 5.3V to the Kiwi sounds a bit agricultural but I have unintentionally fed much more than that into the Kiwi (not Beaglebone direct) over an extended period without issue.
Unless you are going to use sense wires in production I'd tweak the supply up to that. A good few of those who post on the forum set the supply above ~5.2V to reduce the chances of issues caused by brown out as described in the quick start. There is DC filtering and traces before it gets passed to the BeagleBone.

Power the lambda on, tweak to 5.2-5.3V, connect only one Kiwi, report back.