Archive for February, 2011

Setting the date on a Muvi Micro Camcorder

Sunday, February 27th, 2011

I recently got a little Veho Muvi Micro Camcorder after seeing my brother using one on his bike. I appear to have the Pro model which on the positive side can handle more frames per second, but on the negative side puts a bright green timestamp on your recordings and there’s no way to disable it.

So the best you can do is at least make sure the timestamp is correct; it will reset to some known epoch if the battery goes flat and it might lose accuracy over time although I can’t say I’ve paid attention to that. There’s a utility for Windows that ships with the device, but that’s no good on a Mac or Linux host so for the benefit of the lazyweb and myself because it’s fairly obscure how to do it…

Create a file called time.txt in the root of the Muvi filesystem (alongside the DCIM directory) with the following contents:


Unmount the device and turn it off and on, the file should be consumed and the time should be now set.

Here’s a video shot in my 1955 VW Beetle which demonstrates the annoying timestamp, although does show the Muvi does just about cope with the electromagnetic interference from the magneto ignition and noise levels from the exhaust, although it doesn’t cope with the lack of daylight, blame the black paint for that.

Holy Exploding Batteries Batman

Sunday, February 27th, 2011

If you have a UPS, it’s probably worth paying attention to the temperature reading if it reports such a thing. My APC Smart-UPS 1000VA suffered a failed battery which wasn’t totally unexpected given I had last replaced it about two years ago.

While I was awaiting the replacement RBC6 battery, I had a poke about with apcupsd and noticed that it reckoned the internal temperature of the UPS was around 39-40 ℃ which seemed a bit high.

New battery arrived so I pulled the front panel off the UPS and tried to use that stupid plastic flap APC put on the battery to help you pull it out, surprise, it tore off like it’s done on every damn battery. Okay, so I’d have to reach in and get my hand behind the battery to push it out, which due to the nature of what a UPS generally does felt like that bit in the Flash Gordon movie when Peter Duncan sticks his arm in the tree stump and gets fatally stung. Nope, still not coming out and I could feel the battery was quite hot so I pulled the power and left it to cool down for an hour or two. With a bit of help from gravity it became apparent why the battery was being so stubborn:

Bursting Battery

The photo probably doesn’t illustrate just how distorted each side of the battery was. According to apcupsd the temperature is now around 25 ℃ with the new battery so it’s probably worth sticking some monitoring on that. Grabbing the temperature is easy if apcupsd(8) is running:

# /usr/sbin/apcaccess | grep -i temp
ITEMP    : 25.9 C Internal

It should be easy enough to wrap that in a simple Nagios test and/or graph it with Cacti.