Overnight WSPR at 28MHz

Intrigued by recent evenings' results at 14MHz WSPR, I decided last night to keep things going up at 28MHz.

Antenna in use was a vertical delta loop cut for 14MHz, operated at its first harmonic, at which frequency the radiation pattern is a 'bell', with high horizontally polarised lobes, and low vertically polarised lobes.  Unlike at 14MHz, the 28MHz pattern has a more directional, pseudo-dipole nature:

14MHz vertical delta loop radiation pattern when used at 28MHz.

Total number of received spots here between 19:20UT and 06:20UT was 78.

It was nice to see FY5KE hearing my 1W twice in the earlier part of the evening, across an all-sea path.  My 1W was heard at a very good -17dB (20:18UT), compared to M0UNI's -23dB from 10W, and G8CQX's -25 at 20W around the same time.

Spots I received (red) and I sent (green), 19:20-06:20UT 28-29 August 2019, 28MHz.

The only station that kept coming in all night was OH5XO.

I was interested to see if there was any evidence at 28MHz of the very brief, strong and repeating spikes in signal strength seen at 14MHz recently.  The rationale for this was that the cause of the spikes might be Es.

Whilst there were peaks and troughs developing over longer periods, there was no evidence of these very sharp spikes on this evening (28-29 August 2019) at 28MHz.  Here are the stations that provided sufficiently long datasets to draw a reasonable plot:

First, OH5XO, sending 200mW:

OH5XO received by MW1CFN, WSPR at 28MHz.

OZ7IT, sending 5W:

OZ7IT received by MW1CFN, WSPR at 28MHz.

IK1NET, sending 200mW:

IK1NET received by MW1CFN, WSPR at 28MHz.

ZB2TEN, sending 100mW:

ZB2TEN received by MW1CFN, WSPR at 28MHz.

And, finally, how LA3FY/2 heard my 1W output, which is perhaps more spiky than my received signals, although this is mostly in the context of a developing pattern over a longer time span:

MW1CFN received by MW1CFN, WSPR at 28MHz.