Sunday, June 3, 2018


Please find below, Brother Zyg's VOACAP work related to WINB DRM testing (updated with information from Hans about their Rhombic being terminated)


WINB reports : 
"We are testing in DRM 15670 kHz M-F 
try between 1100-1700 UTC"

Here is a preliminary view of the WINB 15670 kHz DRM coverage at 1600z for June 2018.  The coverage is for a receiver using only a 6 foot whip antenna.  Higher gain antennas may produce better results.

The WINB Rhombic antenna parameters are taken from the HFCC files.  Although the transmitter has been stated as "being rated for 15 kW", I'm using a conservative estimate of 10 kW DRM power for the plot. 
From SWL reports the transmitted bit rate has been monitored as being 8.28 kbps, which should help it to be decoded at lower signal levels.

A report in the DRM RX forum indicated that the signal was relatively strong in Newfoundland at this time but with deep fading and then disappeared some minutes later.  This agrees with the plot which shows the listeners location just on the edge of stronger signal coverage.  The propagation does move the stronger signal area eastwards as time progresses.  There were also reports from the UK and France at a little earlier time when the signal would have been at a somewhat higher level in those areas before moving eastwards.

On Friday, I monitored the KiwiSDR web network of receivers at 1600z and found 15670 kHz DRM "waterfall" signals in Houston, Miami (stronger), and Iceland (weak).  I did not encounter any DRM signals in Europe at that time, but Radio France International has a 500 kW broadcast from Issoudun, France, beaming south to Africa on the same frequency and at the same time!  There was also a much weaker, but still noticeable, signal in the Atlanta area (as received on my Kenwood R-1000 receiver and a long wire antenna).

The plot only shows signals that are stronger than S6 (on an S-meter).

Finally this coverage is for "normal" propagation conditions which just happen to have a zero solar sunspot number as we are in the bottom of the 11 year solar cycle.  Conditions have been less than normal in the past few days.