Charts of Reception of the UK 5MHz Beacons 5290KHz by G4ZFQ at IO90IR

Latest Charts of Reception of the UK 5MHz Beacons 5290KHz by G4ZFQ at IO90IR, Cowes Isle of Wight. South Coast of UK.

Now Here:- http://g4zfq.host-ed.net/5MHzBcon/RAL=Weekly.htm

From May 2007 a "Softrock" SDR receiver has been used, Peter's software accepts the I/Q signals. These simple crystal controlled "receiver front ends" seem to work well. I have kept some early charts which show changes.

Note! Peter, G3PLX has now modified the monitoring program to give a TX inhibit signal during the beacon times.

I realised that the preamp I was using was being affected by the strong VHF signals here. At around 5MHz the noise level was high, a 30MHz cut-off LPF reduced this.

12.00 on 18 May Si570 Softrock installed.

15.00 3 Aug. to 16.00 5 Aug. various tests. The two lowest noise readings are with dummy load. 11.40 4 Aug to 14.15 5 Aug. Preamp removed, program adjusted 8db to compensate. Noise floor seen to be higher, almost 8db preamplification is needed to see local antenna noise.

Softrock installed, the preamp enhances the signal/noise ratio in the daytime when background noise is lower. Charts now compare with previous results using Icom R70. Note:- This is an early Softrock used with a low quality on-board sound card. Up to date Softrocks used with a reasonably low noise card should not need preamps.

Images are .png format, Text added to the .gif and saved as PNG using IrfanView. Gives similar quality but less than half file size. IrfanView offers a batch conversion between many types.

My charts are produced by my crude implementation of Excel. If you have Excel and are more of a beginner than me click this for information.

Information about the Beacons - Index

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