QRP Labs
Low power QRSS beacon PDF Print E-mail
Written by Hans Summers   
Saturday, 20 June 2009 17:01

This ultra-low power QRSS beacon was designed to be as efficient as possible, and produce a milliwatt or few from low voltage, low current supply. My intention was to investigate the use of natural power sources to operate the beacon.

QSL card!

Steve G0XAR visited the G0UPL shack and took some photos of proceedings. Combined with a sneakily obtained photo of G0UPL sleeping somewhere in Texas en-route to Ozarkcon 2007, G0XAR produced this very nice QSL card suggestion!

First, the construction. It uses a single BC107 transistor as oscillator (no power amplifier!) and two further BC107 transistors as an astable oscillator to generate a distinctive FSK pattern with about 20 seconds period. I use a piece of tin can for a circuit substrate. Read More...

Measurements of the performance (Power output, and Efficiency) with respect to supply voltage, and base-collector resistor. Read More...
First Reports, 01-Jan-08 - 09-Jan-08.

No reports from my 30m crystal. So on New Year's day 2008 I changed to a 7014kHz crystal and started receiving reports. Read More...
7,000,850 Reports, 10-Jan-08 - 31-Jan-08.

Later on 10-Jan-08 I received a 7000kHz crystal from Peter DL6NL and was able to the favoured 7,000,850 +/- 50Hz sub-band on 40m. Read More...
Homebrew bleach battery.

Research on homemade batteries to power my QRSS beacon started with lemons, and culminated in the development of this 4-cell battery made from baked bean cans, copper wire and bleach. Read More...
7,000,850 BLEACH power reports, 01-Feb-08 - 06-Feb-08.

Shortly before midnight 01-Feb-08 the beacon power source was switched to bleach power, producing 3mW output. On the first day, I received reception reports from three stations, G3VYZ, ON5SL and GM0RZY! Read More...
An ode to QRSS - 30m beacon by G0XAR

Steve Farthing G0XAR built this beacon project for 30m, and we put it on air during a visit on 12-Jul-08. Despite a few difficulties Steve got reports from G6AVK and I2NDT! Steve's ode to QRSS follows (allow for a little poetic licence!) Read More...

Last Updated on Wednesday, 24 June 2009 19:37
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