Radio Reflections received in Bangor, Northern Ireland

Richard - Gi4DOH - North 54° 38' 23" West 5° 41' 22"

Information

The aim of this project is to detect meteors entering the earth's atmosphere by detecting reflections of radio waves off the ionised trails that they leave for a short duration. By tuning into high power VHF transmitters that are normally too far away to be received, it is possible to detect bursts of radio reflections from these trails (around 85-105 km up).

Originally my hardware consisted of four Icom PCR-1000 receivers and an M-Audio Delta 44 soundcard. The antenna was a wide band discone split between the receivers with a low-noise pre-amp providing about 10 dB gain to offset the loss of the passive splitter.

Hardware Configuration

Figure 1: Original System Configuration

Unfortunately, VHF TV stations are becoming history and Skalafell in Iceland is the only transmitter providing a suitable RF source for me at the moment. My current onfiguration is shown below.

Hardware Configuration

Figure 2: Current System Configuration

Software Purpose
Windows XP SP2 Operating System
DL4YHF's Spectrum Lab v2.7 b19 Audio Signal Analyser
PCR Pro v1.12.254 Beta Controlling Icom PCR receivers
APBackUp v3.2.5073 FTP/Backup tool
QuickMix v1.06 Audio Mixer Settings Tool
Batchrun v4.0.1.5 Batch file application used for auto startup
NISTIME Synchronise PC clock with NIST Network Time Service
Crimson Editor v3.70 Excellent g eneral purpose text editor
PHP/SWF Graph v4.7 Web graph tool

Table 1: Software Configuration

Seven different instances of the 'Spectrum Lab' software are running and these record the following:

There are also some other things that can cause signals to be detected. I hope to display examples in the near future of some of the typical events that get recorded with a description of what is going on.

The counting algorithms that I use are quite basic and are prone to distortion by many different types of interference both man-made and natural. Also, the counters have a tendancy to saturate during periods of high meteor activity

I can be contacted at richard@ramfihaz.co.uk