The new "BEACON ROBOT" made by radioamateurs

February 1997

Version: 1.0

Summary Specifications:

Nominal Frequencies:
28195.00 kHz - 24920.00 kHz

Site.
Pontecchio Marconi - Bologna - ITALY - Locator JN54OK, 400m a.s.l.

Modulation:
A1A (CW) - A3b (SSB), PACKET (only the controlling station).

Transmitter:
TX with PLL control of the frequency stability (+/-2ppm) and RS232 serial interface control. Output power control modified.

Output power:
Fixed at 32W during identification. It can be varied in 3 dB steps from 32 down to 0.125W, at user command.

Receiver:
Double conversion configuration, programmed for the radioamateur 10, 12, 15, 17m bands.
Sensitivity :<0,25 (V per 10dB S/N.
Bandwidth : 500Hz (CW), 2400Hz (SSB) at -6dB.
RS232 serial interface control.

ADC, DAC Conversion:
10bit resolution to control theoutput power and read internal and external temperatures.

TNC:
PACKET communication module at 1200 bps SSB, only from the controlling station.

Power Supply:
Switching type, 12A at 13.8V.

Antenna:
half-wave multiband vertical .

Computer:
CPU 486 DX33 MHz, 4Mb RAM, 720 Kb static RAM disk with back-up battery.

CW Demodulator:
Active filter with switched capacitors.

Software:
Almost 11.000 code lines in Borland Pascal, under DOS.

Main Memory Capacity:
2048 QSO. Each qso record is made by 8 fields: date, time, callsign, operator's name, received S-value of the signal strength, sent S-value, output power level of the Beacon and frequency.

Callsign Database Capacity:
2500 callsigns, with operator's name and date of the last QSO.

Command keys:
44 commands in CW for users, 68 commands in PACKET, only for the control station.

Automatic recognition of CW speed:
From 10 to 60 WPM (50 to 300 characters / min.).

Received Signal strength scale:
From S1 to S9+20 dB. Calibrated from 0 to 54 dBuV, in 1 dBuV steps
(S9 = 50 uV = 34 dB uV).

Identification Cycle (ID):
__ . . . ____ . . . __ IY4M IY4M
__ . . . ____ . . . __ IY4M IY4M
MARCONI MEMORIAL BEACON ROBOT QRV QRV

Stand-by period:
after every ID cycle, the Beacon Robot is switched into the receiving stand-by mode, for 30 seconds.

Functional goals:
Monitoring of the long range propagation of radio waves in the amateurs band of 10, 12, 15, 17m.
Careful determination of the user's antenna pattern and receiver S-Meter scale, through the accurate calibration of the signal strength received by the Robot and of its output power.
Versatile operation of many different features.
Archive of more than 2000 QSO, each recorded with all their relevant data.
Broadcast of general interest messages.
Celebration of the experimental work done by Marconi.