Since Monday the 2nd, storm watchers have been viewing Hurricane ETA-20 with alarm as it bears straight down on Nicaragua from its East. At first wind-speeds of 185 km/h were forecast and 133000 people were in the red zone of danger in front of the category one hurricane. By Thursday, wind-speed forecasts were upped to 240 km/h, and Honduras was also predicted to be in its path.
On Tuesday, Greg G0DUB reported that the Emergency Services of Radio Amateurs and Emergency Networks were active in Nicaragua, Honduras, and Guatemala, using HF comms on 7098, 7120 and 3798 kHz, as well as DMR Talkgroup TG710. Amateurs are asked to avoid these frequencies if they do not have emergency traffic to pass.
The ARRL reported on Tuesday that WX4NHC at the National Hurricane Centre (NHC) activated, monitoring 14.325 MHz and 7.268 MHz, the frequencies used by the Hurricane Watch Net (HWN), as well as the VoIP Hurricane Net, Winlink, APRS, and other modes.
As of 21h00 UTC on Tuesday, the eyewall of what the NHC was calling “extremely dangerous Hurricane Eta” was making landfall just south of Puerto Cabezas, Nicaragua. The NHC warned of a life-threatening storm surge, catastrophic winds, flash flooding, and landslides across portions of Central America. Eta was moving to the west at a rather sluggish 5 km/h. The NHC said Eta was forecast to move farther inland over northern Nicaragua through Wednesday morning, and then across central Honduras by Thursday morning.
“This will be another historic hurricane to hit this area during a historic active season,” said Assistant Amateur Radio Coordinator Julio Ripoll, WD4R, at the NHC.
Ripoll asked stations to relay any reports from stations or ships at sea in the affected area, with or without weather data, for use by NHC forecasters.
“NHC appreciates all the surface reports from the affected area during hurricanes as they fill in gaps of not just weather data, but also give them real-time, first-person perspective of what is actually happening on the ground,” Ripoll said.
News reports on Saturday afternoon report as many as 2150 deaths so far.
Grant Southey ZS1GS, National Director of HAMNET, has invited his Regional Directors and their deputies to attend a virtual meeting on Wednesday the 18th November. Subjects to discuss include feedback from the National Director, ongoing projects and new memberships. I wish them well in their deliberations next Wednesday.
The weekly ARRL Letter for 5th November says that Researchers at the National Institute of Standards and Technology (NIST) have devised and demonstrated a system that could dramatically increase the performance of [fibre-optic] communication networks while enabling record-low error rates in detecting even the faintest of signals. This has the potential to cut the total amount of energy required for state-of-the-art networks by a factor of 10 to 100. The proof-of-principle system consists of a novel receiver and corresponding signal-processing technique, entirely based on the properties of quantum physics and able to handle extremely weak signals with pulses that carry many bits of data.
“We built the communication test bed using off-the-shelf components to demonstrate that quantum-measurement-enabled communication can potentially be scaled up for widespread commercial use,” said Ivan Burenkov, a physicist at the Joint Quantum Institute, a research partnership between NIST and the University of Maryland. Burenkov and his colleagues reported the results in Physical Review X Quantum.
“Our effort shows that quantum measurements offer valuable, heretofore unforeseen advantages for telecommunications leading to revolutionary improvements in channel bandwidth and energy efficiency,” Burenkov added.
Modern communications systems work by converting information into a laser-generated stream of digital light pulses in which information is encoded — in the form of changes to the properties of the light waves — for transfer and then decoded when it reaches the receiver. The train of pulses grows fainter as it travels along transmission channels, and conventional electronic technology for receiving and decoding data has reached the limit of its ability to precisely detect the information in such attenuated signals.
The signal pulse can dwindle until it is as weak as a few photons — or even less than one on average. At that point, inevitable random quantum fluctuations, called “shot noise,” make accurate reception impossible by normal (“classical,” as opposed to quantum) technology because the uncertainty caused by the noise makes up such a large part of the diminished signal. As a result, existing systems must amplify the signals repeatedly along the transmission line, at considerable energy cost, keeping them strong enough to detect reliably.
The NIST team’s system can eliminate the need for amplifiers because it can reliably process even extremely feeble signal pulses: “The total energy required to transmit one bit becomes a fundamental factor hindering the development of networks,” said Sergey Polyakov, senior scientist on the NIST team. “The goal is to reduce the sum of energy required by lasers, amplifiers, detectors, and support equipment to reliably transmit information over longer distances.”
Southgate Amateur Radio News has reported that German TV broadcaster WDR aired a news story about radio amateur Theresa DC1TH who is part of the Neumayer-III base 2021/22 overwintering crew.
She is expected to be on-the-air from Antarctica with the callsign DP0GVN using the QO-100 geostationary satellite amateur radio transponder. Theresa DC1TH visited AMSAT-DL at the amateur radio facility at the Bochum radio observatory for some brief training in the use of QO-100 before traveling to the Neumayer III base.
AMSAT-DL provided the QO-100 satellite ground station for DP0GVN nearly a year ago, and it has already been operated by Roman HB9HCF.
It intrigues me that satellite QO-100’s geostationary signal can be heard by stations even at the North and South Poles. I’m sure the Yagi’s needed to complete the QSO’s at 90 degrees latitude need no elevation rotators to access QO-100. In fact their signals might need just to brush the surface of the snow to be received by the satellite!
Finally, Michael ZS1MJT tells me that today’s Jonkershoek Mountain Challenge trail run has had its route altered to a safer one, as a result of a strong cold front with heavy rain and strong winds which has battered the Western Cape since Friday. Northerly winds gusting at 60 km/h at sea level, and nearly an inch of rain between Friday and Saturday, may contribute to treacherous running and dangers of hypothermia in the Jonkershoek pass today.
This is Dave Reece ZS1DFR reporting for HAMNET in South Africa.