This article describes an on air test of the Simple Morse beacon keyer project.
Fig 1 shows the prototype keyer using an ATtinyx4(A) constructed on a small piece of Veroboard. The prototype has a set of DIP switches for selecting message, speed and enabling the on-board sidetone speaker. The six pin header is for AVR programming, and a regulator allows operation on 12VDC. A reset button allows convenient reset for message time synchronisation. This keyer uses a crystal clock oscillator for more accurate timing, allowing "image stacking" as discussed at QRP QRSS Beacon Transmitter - on air.
The transmitter was a TS-2000 running 10W,the antenna is described at Bowral 7MHz dipole for local contacts. The emission type of the signal is A1 (amplitude modulated telegraphy) at QRSS6 speed, and the message text is "VK1OD =" repeated every 10min.
Fig 2 shows a Spectran capture by K1DNR in CT, USA at a distance of 16,220km. The message is not very clear, but timing and frequency changes verify that it is indeed VK1OD. The telegraphic elements in this capture are "VK1OD".
The receive system is a 20m long dipole at 13m height centre fed with hybrid open wire and coax feed lines and a TS-590 transceiver.
The Spectran captures were not well suited to "image stacking".
Thanks to K1DNR for the captures.
Fig 3 shows a stacked image capture at G6AVK in Essex UK at 16,952km.
There is apparently some timing jitter (~5s) in Spectrum Lab in capturing images, as can be seen by the blurring of the timescale marks. Additionally, the time of day appears to be about 40s slow as the VK1OD message begins 10s after the hour and repeats every10 min.
Receiver is a TS-850SAT.
Thanks to G6AVK and W4HBK, stacked image courtesy of W4HBK.
Fig 4 shows a stacked image capture at G6AVK in Essex UK at 16,952km. This is a stack of 6 images from 04:50Z. The clock is showing the correct time in this image. (Images stacked by VK1OD for Fig 4.) It can be seen from Fig 4 that most signals are not enhanced by the stacking technique, and it is because the messages do not repeat on a 10min cycle.
© Copyright: Owen Duffy 1995, 2020. All rights reserved. Disclaimer.