Signal Propagation

[Stanley]

[PanBiker]

The upward climb to the peak of solar cycle 25 continues to enhance the HF bands. I was trolling through the bands last night and managed to contact a station in Uruguay on 17M band (18MHz). He was good signal, not end stopping but peaking at 5/7 throughout the exchange. First contact on SSB into that particular area for me on that band. Had bit of a natter earlier with Kevin down in Gargrave on 2M, no band enhancement by solar activity required for that one.

[PanBiker]

Another feature (or drawback) of increased solar activity is the overall background noise level on the HF bands. The heliosphere currently has a very high number of active sunspots and this and other factors such as a more intense solar wind all contribute to the noise level on susceptible bands. So bad during daylight hours that you are hard pressed to hear any signals above the noise level unless they are running extremely high power! The noise level drops off as the grey line progresses across the globe. This is the transition point between daylight and darkness and means that you still get the enhanced propagation effect and manageable background noise although fading (QSB) can be problematic. Slow QSB is a bit of a menace as you can start a reasonably strong signal contact only to have it fade out before you finish the contact. This is why it always pays to listen first to assess band conditions before putting out general calls or responding to others.

I am also dabbling with a relatively new digital mode, VarAC. This is a digital chat mode, similar to RTTY (Radio Teletype) or Amtor. It has built in error checking and hand shaking facilities. It consists of a controlling front end that drives a software based modem in the background. The front end also interfaces with and controls the transceiver so you can select bands and frequencies via the computer interface. The system automatically keys the transmitter as required.

There is considerably more to it than just that so I have included the link for anyone interested.

VarAC

[Tripps]

I'm a bit interested of course.

Thanks for the info. Nice blend between the old and the new.

[PanBiker]

Made my first contact via VarAC yesterday afternoon on 20M (14Mhz). Had a nice chat with Ernst OE3EJB in Austria.

The HF bands were overall very quiet yesterday as the planet was being battered by a massive interplanetary shock wave from the sun. This, apart from suppressing the HF frequencies triggered a massive auroral event last night. The event is still in progress and there will be chance of visible aurora again tonight in dark sky areas of the UK.

[Stanley]

Still haven't seen the Northern Lights..... Perhaps mainly because of the harses in between....