Equipment - Computer

UFO capture and analysis requires only a modest specification PC but a larger hard drive is a must.

Modified CCTV camera with Fujinon lens

The data acquisition software (UFO Capture) requires only a modest specification PC. In fact, UFO Capture will run happily on an older Windows XP machine which can be picked up for as little as £50 or £60. With an older PC it may be necessary to add a bigger hard disk and increase the available memory.

The minimum specification is outlined in the table below.

Item Minimum specification Recommended specification
CPU Pentium 4 HT, Pentium D (dual core) Core2 Duo, Core2 Quad, AMD APU (tested)
RAM 1GB ram 2-4GB (if you plan to process also on the same computer)
HDD Speed 5400 rpm drive should work but at high meteor rates there may be problems 7200 rpm disc drive
HDD size The bigger the better.  Smaller drives such as 40-80GB will need to be "emptied" more frequently whilst 250-500GB is considered a miminum 500GB - 1TB hard drive
OS Windows XP Windows 7 (works also with Windows 10)

During major shower peaks your camera might record in just one night more than 200 meteors. Each video clip could be as much as 100MB so that's 20GB of data right there. Smaller drives such as 40 - 80GB will need to be "emptied" more frequently whilst 500GB - 1TB will keep you going for a while. Disk of size 250GB - 500GB is considered a working minimum.

PC Configuration

Once you have your PC ready to go, there's a few settings you need to configure.

UFO Capture streams high volumes of data to disk and anything that interferes with this stream can cause corrupted video files. Two common causes of corrupted AVIs are:

  • Power settings
  • Antivirus software

The power settings determines when the PC is able to save power by putting the PC to sleep, putting the CPU into a low power (slow) mode, or powering off devices. Obviously you do not want the PC to go to sleep, but neither do you want the disk to spin down. If the disk spins down, it has to spin up again before video data can be written to disk. Power settings should be changed to disable these power saving functions on the disk and should ensure the computer runs in a high performance mode, even when Windows operating system thinks that the PC is idle.

Note too that we have not have had much success with external USB drives and we suspect bandwidth and power saving features may be at the heart of the problem.

Time and Time Synchronization

Meteor data recorded by UFO Capture includes an event time stamp which is crucial to matching data between stations. It is vital that all PCs in the UKMON record time accurately:

  • Your PC clock should be configured to use GMT and not daylight saving
  • Your PC should be configured to take its time from an Internet Network Time server using the NTP protocol

There are several NTP client programs which can be downloaded for free but the most popular choices are:

Network time synchronisation requires a permanent internet connection which might not be possible (especially if your meteor station is located in a rural area). All is not lost however; time synchronisation can be achieved using a GPS dongle although care is needed. The time synchronisation must be “UTC” and not GPS time (GPS time can differ by many seconds).

Running a PC without manual intervention

It is worth considering your energy bill and keeping running costs down. Ideally your PC should be running only between sunset and sunrise. Depending on your computer's motherboard, you may be able to set up scheduled start-up and shut-down times, If this is not possible then timed shutdown is possible from the DOS command line (using the DOS “at” command).

Maintaining PC Performance

We strongly recommend automatic Windows updates are disabled or scheduled for daylight hours only. There is nothing worse than an update happening in the middle of a clear night.

Regular housekeeping will pay dividends:

  • Clearing out deleted items
  • Defragmenting your disk
  • Applying Windows updates (manually)