The BCC Preselector
The BCC Preselector
In past years of multi op contesting we were
continously suffering from the many different and
exotic designs of peripheral devices at the
operating position. Everyone had his own
standards in keyers, antenna switches and
preselectors.
To improve this situation we came up with the
idea of a BCC standard. So the BCC Institute of
Standardization
(BCCIS) was founded.
The BCC preselector was its first project
to make an end to cooked
attentuator resistors, broken preamp units, shorted switching
diodes and frustrated operators.
Many a contester has developed his own device in the
past years, each of them in a different way with a different
operating and switching philosophy. Using such a device
in a multi-transmitter environment is a must. But is is
difficult to understand how to use it in the middle of the
contest after endless hours of operating. That is how we came
up with this concept.
Using an original design by DL7AV, we placed
easily available components on a PCB and added
a switch for selecting different receive antennas.
The device prevents receiver damage in multi-TX
environments by attenuating out-of-band signals
by at least 20 dB.
50 such preselectors were assembled in the BCC
labour camps (in Eching nr Munich, Bavaria) and
distributed among the BCC membership. They
are being used with continous success by their
proud owners.
Front and backside of the BCC preselector
What we did was: take a simple circuit, make a board and use easily
available parts.
Schematic diagram
50 such units were competely assembled
in the BCC labor camps in Eching (near Munich) during March and
April, 1996. All of them have been sold to BCC members.
However, if you are interested, a very detailed
description in German is available as a PDF file
(504 kB) including PCB schematics, layout etc.
seen from front
BCC preselector, seen from back with board turned overhead
BCC preselector, looking into the housing
Last updated: 06 Jan 2003
-- 15:36 UTC by DL6RAI, DL2NBU
and DF4RD
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