User's Manual

FIREMASTER IV " MillenniumThree " radio shooting system User’s manual
4.7.2 Antennas
1) The antenna supplied with the FIREMASTER IV "Millennium Three",
is INTEGRAL WITH THE INSTRUMENT and it is used the same type
both for the Base Unit TX5000 and the Remote Units RX48. These
antennas are whip type in λ/4 resonating at 40,700MHz. The antenna is
realized completely in fiberglass and aluminum; it is very flexible and
fire resistant. The connection to the Unit is pivot-type one with wing
nut.
2) The antenna is supplied in TWO PIECES: the bottom one is made of
aluminum and is provided with a strain-relief spring and the wing nut. The
top section is a fiberglass whip. The two pieces are quickly mounted simply
sliding the terminal part of the whip section into the bottom aluminum tube.
3) In order to obtain the best results concerning the radio coverage field, even
in presence of natural or artificial obstacles, the Remote Units should be
placed at least ONE METER above the ground. Remember as, consistently
with the terrain type and the show's needs, HIGHER THE ANTENNAS
ARE PLACED, MORE COVERAGE RANGE IS OBTAINED AND
THE SAFETY MARGIN IS INCREASED ACCORDINGLY.
4) The metal parts of the antennas (CONNECTOR, SPRING, WING NUT)
ARE ELECTRICALLY ACTIVE: AVOID ANY CONTACT WITH
ANY OTHER METAL PART OR EXTERNAL WIRING. Avoid also
any contact with the antennas of the next Units and other metal objects. IN
GENERAL: the antennas must be installed in VERTICAL POSITION, far
from any other object by at least 2 meters.
5) The reading of the field strength, in dBµV, displayed on the base Unit
TX5000, give a good indication about the system ability to communicate.
Avoid to operate when the reading is BELOW 15dBµV: it could happen
some problem of partial data decoding with the result of SOME MISFIRE
AT THE FIRST ATTEMPT (IN ANY CASE IT IS ABSOLUTELY
EXCLUDED ANY RISK OF PREMATURE OR UNDUE FIRE!!!).
6) The RX48 case is provided with a COAXIAL CONNECTOR (“UHF” type
SO-239) placed EXTERNALLY near to the handle. This connector allows
direct connection for a coaxial cable when the CABLE connection is
required in place of the RADIO link or when an EXTERNAL aerial (e.g.: a
GROUND PLANE antenna) is preferred in place of the standard antenna
(for very critical propagation conditions). This connector however doesn’t
allow the direct insertion of the standard antenna (provided with a pivot-type
attachment and a wing nut). A SPECIAL ADAPTOR is supplied as
STANDARD ACCESSORY with the Unit: this adaptor allows a direct
connection of the standard antenna but can be very quickly REMOVED if
the SO-239 coaxial connector must be used. When not in use, we suggest to
REMOVE always the antenna adaptor and to place the cover cap on the SO-
239 coaxial connector: this will grant the best protection of the whole Unit
against any possibility of humidity or water penetration inside the case.
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