NEW WORLD 241GHz RECORD - WA1ZMS DOES IT YET AGAIN!
We've just received this email from Brian, WA1ZMs, on what is truly a magnificent achievement ... many congratulations to him!
----Original Message-----
From: wa1zms@att.net [mailto:wa1zms@att.net]
Sent: Tuesday, February 17, 2004 7:23 PM
Hello everyone - I'd like to claim what should be a new World and North American DX record for the 241GHz band.Last night, W2SZ/4 worked WA1ZMS/4 on 241GHz at a distance of 79.6km using slow speed CW (QRSS).
Details of the QSO:
Date: Feb 17th, 2004
Time: 00:15z
Locations: W2SZ/4 in FM07fm (37-31-00N 79-30-35W)WA1ZMS/4 in EM96wx(37-59-28N 80-07-17W)
Distance: 79.6km
The weather at the W2SZ/4 QTH was:
Temp: -8C
Dew Point: -26C
Relative Humidity: 22%
Station pressure: 884mb
Atmospheric loss: 0.273dB/km
The weather at the WA1ZMS/4 QTH was:
Temp: -8C
Dew Point: -16.1C
Relative Humidity: 53%
Station pressure: 932mb
Atmospheric loss: 0.681dB/km
Pete, W4WWQ was the CW op at W2SZ/4. WA1ZMS/4 was the op of his own station at the EM96 QTH. Both ends of the QSO used Spectran software to aid in
receiving the slow speed CW at a rate of approximately 1 second per "dot", 3 seconds per "dash".The entire QSO took well over an hour to complete with both stations having to send the exchangesseveral times. Some portions of the CW were copied by ear, but the DSP software came through in the end to help make the QSO happen.Both stations used new Wenzel Ultra-Low-Noise 5MHz
reference oscillators as the phase-locking frequency references. Short-term stability on the order of 4 x 10-13 is required to keep the signals within a 1Hz filter bandwidth of the demodulating software.The stations were keyed using Island Keyers with custom QRSS firmware from Charles Olsen, WB9KZY.This QSO is also the 5th grid needed for the ARRL VUCC award for the 241GHz band for W2SZ. This claim should be the very first VUCC for that band and has taken many months of hard work and many VERY cold-night DX-peditions to make it all happen.
This latest DX record of 79.6km occurred on our fourth attempt, so we were not without our failures.More information with photos will be posted at www.mgef.org over the next several days.
73, Brian Justin, WA1ZMS
Больше всего поразило не расстояние и даже не частота, а то, что это самодельная аппаратура с синтезатором (!), точность установки частоты которого до четвёртого знака (!) после запятой.
В России темой СВЧ давно и с хорошими результатами занимаются Жутяев и Прокофьев. Не последнее их достижение (надеюсь) - QSO через Луну в диапазоне 47ГГц. Судя по блок-схеме аппаратура не представляет особой сложности, но аккуратности и терпения несомненно требует.
Тема интересная и хотелось бы чтобы и наша страна не отставала от лидеров. Главное - начать. А потому, расчёты конвертера на 5,7ГГц готовы. Передатчиком займусь позже. Как только появится возможность выложить схему на сайте - обязательно поделюсь. Надеюсь за зиму успею его собрать. Есть небольшие достижения в диапазоне 10ГГц - 25км.
73!