Titanic SCR Preselector  

Titanic SCR Preselector

500KHz band (aka Titanic band) tunable Band Pass Filter.

Software Controlled Radio Preselector via USB or I2C bus. Digital tuning.

The only known photograph of Titanic's Marconi room.

Shortly before midnight on 14 April 1912,the RMS Titanic struck an iceberg and sank two hours and forty minutes later, early on 15 April 1912.
Wireless operators Jack Phillips and Harold Bride remained at their posts, even after being released from their duties by the Captain,until about 3 minutes before the vessel foundered, sending out the international distress signal,
CQD “ — • — •   — — • —   — • • "  All stations: distress.
After that terrible disaster the 500KHz band was know as well as the Titanic band.
500 kHz was the international maritime Morse code radio distress and safety frequency for most of the 20th century. It was the frequency used by thousands of ships to signal their trouble in times of peace and war.
With the decline in the use of Morse code on board ships and the move in recent years to satellite communication it is no longer used for that purpose.
On the last years, various countries have looked into obtaining an amateur allocation at 500kHz. It forms a convenient bridge between 136kHz band and the 160m top band amateur allocations.

      CQD CW signal audio clip (mp3 format)

■ Band covered from 480KHz to 515KHz.
■ Digital tuning.
■ High linearity (IP3). Suitable for Software Define Radios.
■ Large toroid cores T225 and T-106 are used.
■ Joined to a VFO can perform tracking tuning function.
■ Its modular design lets an easy implementation on your projects.
■ I2C Bus or USB control modules options.
■ Tin plated enclosure available.

500KHz SCR Preselector response plot.
(click to enlarge)

USB control option

■ PC controlled through graphical user interface (GUI).
■ Full speed USB v2.0 compliant.
■ Plug and Play feature.
■ Runs under Windows 2K, XP, Vista 32 and Windows 7 OS.
(Windows 2K users need to update Framework from Windows Update site)

I2C bus control option

■ 16 bits standard I2C Bus serial bus interface.
■ Support 100Kbits/s and 400kbits/s FAST I2C Bus protocols.
■ Auxiliary Input/Output ports to implement external controls and/or signalling.
■ Up to eight control modules can share the same I2C Bus.
■ Compatible with most microcontrollers.