QRP Labs
30m QRSS junkbox tx PDF Print E-mail
Written by Hans Summers   
Saturday, 20 June 2009 17:29

Transmission details:

QRP 360mW
QRG 10,140,060
QRV 23-Feb-06 1145 UT until 01-Sep-06 2000 UT
QTH IO91VH, 15 miles south of London, UK
Ant Attic Longwire
Msg FSK, 3Hz separation, squarewave with 25 second cycle

Junkbox beacon construction:

This simple 30m QRSS beacon is built entirely out of junkbox parts, the only component purchased specifically for this project was the 10,140kHz crystal. The oscillator is in a polysytrene box made using pieces of packaging material and rubber bands, for protection from short-term temperature fluctuations such as drafts.

Antenna and Attic installation:

I use a full size half-wave dipole (14.2m) in my attic, taped to the roof at about 4 feet (1.3m) above the attic floor. At its centre is an 18-turn balun wound on a T130-2 toroid. The balun connects directly to the transmitter output using 5m of coaxial cable.

First reports, 28-Feb-06 - 02-Mar-06:

David VK6DI reported seeing a plain carrier that drifted around slowly. I thought it could be me, perhaps with a broken FSK pattern generator. I checked the beacon and found the fault. David VK6DI saw me make the change, on the other side of the world! Subsequently reports came from Larry WB3ANQ and Chris DL6JAN the following morning.

Reports, 03-Mar-06 - 01-Sep-06:

On 02-Mar-05, 1800 UTC I added 2,200uF capacitances in parallel with each of the two 470uF period determining capacitors in the astable multivibrator pattern generator. This caused the cycle time to increase to about 25 seconds. The slower pattern is more suitable for DX listening.

Special Reports:

These are some unusual reports, showing interesting propagation conditions, unusual QRSS monitoring situations, etc.

30m QRSS Receiver:

Don't miss this related project: a simple 2-chip 30m QRSS crystal controlled direct conversion receiver powered with +5V from a computer's USB port!


Reception map:

This map shows the worldwide reception of the G0UPL junk box beacon. Not all stations are shown on the map since some are geographically close to each other so overlap on the map. A full list of receiving stations is listed below. CLICK THUMBNAIL (left) to see larger photo

List of receiving stations

Currently reports have been received from 45 stations as follows:

CallsignNameLocatorDistanceLocation1st ReportNotes
1.VK6DIDavid IseleOF88CD Mount Helena, Australia28-Feb-06
2.WB3ANQLarry PutmanFM19RC Pasadena, Maryland, USA28-Feb-06
3.DL6JANChristian ProehlJO60KU Chemnitz, Germany01-Mar-06
4.ZL4OLMike McAleveyRE54GG Waitati, New Zealand01-Mar-06
5.ON5SLPierre 01-Mar-06
6.LA5VNASteinar Aanesland Aas, Norway01-Mar-06
7.ON4LPErik PlatteeuwJO11OE Brugge, Belgium02-Mar-06
8.I1DFSPaoloJN54AC Italy03-Mar-06
9.LA9BEATj�rand BaugeJO29OG �krehamn, Norway04-Mar-06
10.IW0HKAndrea BorgninoJN61FV Rome, Italy05-Mar-06
11.IOSKKAlex Rome, Italy14-Mar-06
12.OE5EEPHeinz Schnait Seewalchen, Austria16-Mar-06
13.I0CGGiuliano Rieti, Italy30-Mar-0680km East of Rome
14.IK4GBUValeri Bianchi Casalecchio di Reno, Italy31-Mar-06
15.G3VYZLes ThompsonIO95FB Tyne & Wear, UK10-Apr-06
16.PA1SDBPeter KnolJO33KH Appingedam, Netherlands10-Apr-06
17.IK4IDPAndrea TommasiJN54QL Castenaso, Italy20-Apr-06
18.IV3XYMAlessandro VitielloJN65SU Ronchi dei Legionari, Italy21-Apr-06
19. Giuseppe Bini Italy21-Apr-06
20. Giuseppe Bimbi Italy21-Apr-06
21.IK2JETAlberto Scanzi Lonato, Italy22-Apr-06
22.G3GKIVic Kershaw Scarborough, Yorkshire, UK23-Apr-06
23.IZ1KGLGiulio Torino, Italy23-Apr-06
24. Andrea Lawendel Milan, Italy23-Apr-06
25.I2NDTClaudio MaregaJN45TQ Italy24-Apr-06
26.DJ2LFWalter StaubachJN59NO Erlangen, Germany26-Apr-06
27.G0UPLHans SummersIO91VH0.005kmKingswood, Surrey, UK29-Apr-06
28.IZ2KQPEnrico Mese, Italy29-Apr-06
29.DK5NAMichael PetersJO42BH Germany30-Apr-06
30.IK1ZYWPaolo CraveroJN35TC Italy04-May-06
31.ON6RRStaf Rans Belgium07-May-06
32. Hartmut WolffJO52HP Germany07-May-06
33.IW3SGTAlessandro KosoveuJN65VP Trieste, NE Italy08-May-06
34.IZ2EEQMatteo Italy09-May-06
35.SM6LKMJohan Bodin Sweden11-May-06
36.M0AYFDes KostrycaIO93OJ Gainsborough, UK20-May-06
37.G6AVKColin ThomsonJO01HO66kmRayleigh, UK23-May-06
38.G4KKIBill StevensonIO83TM Swinton, Manchester, UK23-May-06
39.IN3KLQGiulianoJN56RG Italy15-Jun-06
40.G7IZUAndrew SmithIO70WK Plymouth, UK29-Jun-06
41.2E0KNJJohn Knott Wells, Somerset, UK09-Jul-06
42.IZ8GFQQuirino TirelliJN71JD Benevento, Italy21-Jul-06
43.I2PHDAlberto di BeneJN45SL Casirate, Italy24-Jul-06
44.N3TFMTodd PutmanEN72FH Kalamazoo, Michigan, USA24-Jul-06
45.AA4XXPaul StroudFM05QR Raleigh, NC, USA30-Aug-06

Two maps from from Larry WB3ANQ showing the path between G0UPL and Todd N3TFM: (click images for the full size versions).


Knights webpages:

VK6DI David
WB3ANQ Larry
DL6JAN Christian
IW0HK Andrea
I0SKK Alex
OE5EEP Heinz
AK0B Stan
G6AVK Colin
G7IZU Andy
I2PHD Alberto
G4OEP Andy

QRSS Information and QRSS Knights mailing list:

QRSS Knights mailing list
QRSS Knights website

QRSS Software:

ARGO: the most popular QRSS viewer program

Propagation pages:

Digisonde - current propagation
Propagation theory pages by G4NSJ
Earth Viewer
Freeware propagation prediction program

Construction aids:

Mini ring core calculator
GQRP club guide to harmonic filters


DB6NT crystal heater (extra stability for your beacon!)

Peter DL6NL has a QRSS frequency HC49 crystals for sale. He has the following frequencies: 7.000, 7.020, 10.137 and 10.140. Price is 5 Euros for three crystals, including shipping. Email him at his AOL address:

Beacon keyers:

Last Updated on Tuesday, 23 June 2009 18:40
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