еще один анонс о работе Австралийца:
Hello everyone,
A brief note to advise that our re-purposed NDB station, VK6MJM, will be operating during the period 20-25 Sept. See QRZ for a little background on the station.
For this second "campaign" week we'll be doing a number of upgrade and installation activities during the day, with the intention of running the station during the night - probably from around 1000 - 2400 UTC. By my reckoning this gives at least a couple of hours of common darkness with the UK and some overlap with most areas of the US (see e.g.
https://academo.org/demos/day-night-terminator/). Significantly, we hope to have mains power available this time around, greatly simplifying logistics. We'll also be testing the Optus 4G/LTE internet link, enabled by a small LPDA directed at a cell tower in the nearby town of Manjimup.
Most activity will involve 630 m and, as well as the Zachtek exciter we used for the first visit I'll be taking my TS-590S, giving us a QSO mode capability (although we may not have much in the way of a separate receiving antenna for this trip). I also want to try some 2200 m transmissions, having previously verified that the coupler variometer will resonate the 22.5 m mast at 137 kHz. To facilitate this goal I've built a new matching transformer to replace the existing Southern Avionics Company unit, allowing greater matching versatility for resonant impedances above 30 ohm. Given the 200 W power limit of the SAC Litz wire coil and the antenna parameters we expect to radiate a little less than 1 W EIRP on 2200 m. It's likely that in the future the 2200 m tuning system will be upgraded.
For beacon transmission modes we'll probably favour WSPR and FST4W-300, based on regional activity preferences. However, the stability tests I've done so far indicate that the TS-590S with TCXO is OK for longer transmissions, although those off-air tests are complicated somewhat by a distinctly non-gaussian noise floor at my city QTH. I'd be interested to hear the experiences of other TS-590S/SG users but local tests involving my TS-890S's receiver (which definitely has the requisite stability) are promising.
As always all spots and reports are welcome, and hopefully the spring weather (and the declining local covid numbers) will allow us to make some further progress.
73, Peter.
