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CHAPTER 9.1

2200m Paths – Short and Medium

Operator Experience

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Chapter 9.1

2200m Paths – Short and Medium: Operator Experience

[See Appendix I-A for SNR sequences on short and medium paths.—Ed.]

3/24/18 ANALYSIS OF 2200M DISTURBANCE WITH RELATIVE SNR REVERSAL AND

ACCUMULATED SNR DIFFERENCE SHOWS WAVELIKE POSSIBLE TRAVELING

IONO-DISTURBANCE (GRAPHS SLIDE)

From Fred K1YQP to: Jim W5EST. Sent: Sat, Mar 24, 2018 5:05 am

Subject: Antenna pattern seen in propagation

...looking at some of the WSPR database for XND and XXP on 137 kHz last night. We had the

rare opportunity to decode simultaneously two stations virtually co-located, with identical

EIRP, but with markedly different antenna patterns in the elevation plane (T antenna for XND vs

tower for XXP), thus irradiating the ionosphere differently.

It seemed to me that I was seeing considerably lesser fades in XND with his presumably

greater radiation at higher elevation angles.

I sometimes decoded a weaker version of either station at a 2f1 - f2 [frequency] but it was

impossible for me to determine whether RX overload on my end or reception/mixing/re-radiation

by one of them. I turned off my preamplifier at 0754z.

2200m TXs W/E to RXs W/E: WH2XXP, WH2XND—kk6eew, k1yqp RXs

Jim W5EST replied: I'm especially considering the 50 point subsets of their WSPR bars that

were sent in the same time slots.