Repeater Levels
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Repeater Signal & Noise levels

Data taken from a simple folded dipole antenna, loft mounted.  Measurements made on an ICOM IC-R8600 with a custom program.  
Noise and signal levels are made from multiple measurements with the median value being plotted.  For noise, multiple multi-sample 
runs are taken and the lowest median plotted.  For signal the repeater is triggered on and the highest median plotted.

  • Updated daily, usually before 07:30 local time.
  • Spot values are plotted with a 7-day average trend line.
  • The hardware for GB7EU was changed sometime between 2020-Apr-28 and 2020-May-03 resulting in a level change.
  • Something unknown happened to GB7SQ between 2020-Nov-30 and 2020-Dec-02 dropping the level by ~3 dB.
  • A local source of interference (wireless doorbell chimes) was removed after 2021-Nov-23 massively reducing noise.
  • Antenna work on GB3ED and GB7EE on 2022-Jun-08 resulted in much stronger signals here - I was in a null before!
  • 2022-Aug-22: Issue with GB7SQ, temporary antenna from 2022-Aug-31.
  • 2022-Sep-05: changed part of my local cable run, perhaps 1 dB signal increase.
  • 2022-Sep-07: Intermittent unknown weak carrier on 430.9205-430.9208 MHz makes accurate noise level on GB7EE impossible.
  • 2023-Apr-18 - GB7SQ returned, but at a lower signal strength at this location.


  • Judging from the levels above, it seems that SNR is driven more by the noise than the signal level, 
    although both GB3ED and GB7EE do show a gradual level change.


  • Noise is the simple average of the four dBm levels measure individually.


  • Averaged noise levels versus the day of the week.  Not sure there's a lot to lean from this?  A better presentation would be nice, but my Excel isn't really up to it!


  • Before lockdown, there was a clear pattern of lower noise at weekends.  As the antenna is in the middle of a housing estate
     the noise pattern will be different to a more industrial location.  This is a snapshot - it is not updated.


Copyright © David Taylor, Edinburgh   Last modified: 2023 Apr 18 at 05:21