FT-950
Operating Manual
Vertex Standard Co., Ltd.
11
impedance at the desired operating frequency. While minor excursions from the
50-Ohm specification are of no consequence, the transceiver’s Automatic Antenna
Tuner may not be able to reduce the impedance mismatch to an acceptable value if the
Standing Wave Ratio (SWR) present at the Antenna jack is greater than 3:1.
Every effort should, therefore, be made to ensure that the impedance of the antenna
system utilized with the FT-950 be as close as possible to the specified 50-Ohm value.
Note that the “G5RV” type antenna does not provide a 50-Ohm impedance on all HF
Amateur bands, and an external wide-range antenna coupler must be used with this
antenna type.
Any antenna to be used with the FT-950 must, ultimately, be fed with 50 Ohm coaxial
cable. Therefore, when using a “balanced” antenna such as a dipole, remember that a
balun or other matching/balancing device must be used so as to ensure proper antenna
performance.
About Coaxial Cable
Use high-quality 50-Ohm coaxial cable for the lead-in to your FT-950 transceiver. All
efforts at providing an efficient antenna system will be wasted if poor quality, lossy
coaxial cable is used. This transceiver utilizes standard “M” (“PL-259”) type connectors.
Grounding
The FT-950 transceiver, like any other HF communications apparatus, requires an
effective ground system for maximum electrical safety and best communications
effectiveness. A good ground system can contribute to station efficiency in a number of
ways:
It can minimize the possibility of electrical shock to the operator.
It can minimize RF currents flowing on the shield of the coaxial cable and the
chassis of the transceiver; such currents may lead to radiation which can cause
interference to home entertainment devices or laboratory test equipment.
It can minimize the possibility of erratic transceiver/accessory operation caused by
RF feedback and/or improper current flow through logic devices.
An effective earth ground system may take several forms; for a more complete
discussion, see an appropriate RF engineering text. The information below is intended
only as a guideline.
Typically, the ground connection consists of one or more copper-clad steel rods, driven
