Decimator micro-USB guard
A guard for the SDI end of a micro-USB Decimator MD-LX, so a tug on the lead doesn't lever the port.
What it does
Before the USB-C version, the MD-LX took its power through a micro-USB socket on the SDI end, in exactly the same spot. Micro-USB is the more delicate of the two, and it was never meant to have a converter swung about by it.
This is the Decimator USB guard redrawn for that model: the same plate over the SDI end, held on by the MD-LX's own two end screws, with the tower round the plug made smaller to suit a micro-USB moulding. The plug can't back out more than about a third of a millimetre or be levered about, and a window keeps the small hole between the BNCs clear.
Where it stands
v0.1. I've modelled it and checked it in software, but I haven't yet printed one and fitted it to a real MD-LX. The steps below are written from the model, and the plug's size comes from photos. Once one has been on a real one, I'll update this page with anything that turned out differently.
Print your own
Fitting it
You'll need
- A screwdriver that fits the MD-LX's end screws
- The micro-USB lead you'll be using with it
Check your micro-USB plug first. The pocket is sized for the flat moulding with a "B" on it that Blackmagic's and Decimator's stock leads use, measured from photos. A bigger moulding won't go in, and a much shorter one can back out a little before the guard stops it.
- Plug the micro-USB lead into the MD-LX.
- Take out the two screws at the ends of the SDI end panel. Keep them: they go back in through the guard.
- Slide the guard down over the BNCs and the plug, so the cable comes up through the open top of the tower and the plate sits flat on the panel.
- Put the two screws back in through the guard. Their heads sit flush in its countersinks. Tighten them until they're snug and stop there: the countersinks are plastic.
How it holds
Two lips at the tower's open end close in over the near end of the plug body, and the back wall leans in over its far end, so the plug can't back out. The walls hold it on three sides and the lips on the fourth, so it can't be levered either.
Two micro-USB revisions
Retailer photos show two micro-USB MD-LXs, the same apart from an extra screw just above the socket on the later one. It sits in a countersunk seat, so the plate covers it flat. If yours stands proud of the panel, the plate won't sit down: let me know and it'll get a recess.
The BNC holes
As on the USB-C guard, the two BNC holes overlap at a waist, because the flanges are too close together for a web between them. A straight-on photo of the micro-USB model puts its BNCs within about half a millimetre of the USB-C guard's numbers, and the holes have 1.2 mm of clearance.
Will your leads fit?
| Micro-USB plug moulding | Up to 10.6 × 6.8 mm across |
|---|---|
| Moulding length | 13.2 mm from the panel to where the boot starts |
| Cable | Up to about 4 mm, between the lips |
Sized for the flat "B" moulding on Decimator's stock micro-USB lead, measured from photos. Try yours before relying on it.
Taking it off
- Take out the two screws.
- Slide the guard off the BNCs and the plug.
- Put the screws back in the MD-LX.
What's been checked
In software only, against the model. Nothing here has been tried on a real part yet, which is what the second list is for.
in software Nothing comes within 0.9 mm of either BNC flange, all the way up, and the small hole between them is left open.
in software Both screw heads seat flush in their countersinks, with room for a screwdriver above them.
in software A 10.6 × 6.8 mm plug body goes in, and it can back out at most 0.35 mm before a lip or the back wall stops it.
not yet The plug's real size, and whether your micro-USB lead fits the pocket.
not yet Whether the extra screw above the socket, on units that have it, sits flush.
Where the numbers came from
The plate, the screw holes and the BNC holes are the Decimator USB guard's, which has been test-fitted. A straight-on retailer photo of a micro-USB MD-LX puts its socket where that guard's pocket is, to a fifth of a millimetre.
More views
Fitted one?
Tell me how it went
If you've put one on a real MD-LX, I'd like to hear about it, good or bad: whether it seated, whether your plug went in, and anything that got in the way.