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B–2
3.3
Initial Installation Considerations
When selecting the place for operating the PT-8000 bear in mind the general limitation concerning
environmental conditions as outlined in the specifications and the cautions at the very beginning of this
manual.
Select a power outlet that is capable to handle the power requirements especially for the PT-8000B.
Connect your PT-8000 to a proper ground system – which is important for optimum operation of any HF
transceiver – especially when operating high power either with the PT-8000B or using an external
amplifier. In the past, a ground connection to a copper water pipe was often used for this purpose.
Recent revisions to the National Electric Code has made this practice a code violation. Bear in mind that
modern supply water installations utilize plastic pipe – which do not function grounding purposes. Never
use a gas or electric pipe since the connection could cause an explosion or electric shock.
A good grounding system not only prevents electrical shock but also helps to ensure trouble free
operation and will diminish television and broadcast interference (TVI/BCI).
For your convenience you might raise the PT8000 and the HN-8000 by unfolding and locking into
position the front stand under the cabinet as shown on the picture.
Allways handle the PT-8000 with care – consider the weight of more than 50 lbs, please!
3.4
Antenna Considerations
Standing wave ratio (SWR) may increase significantly when using an antenna outside of the specific
frequency range for which it is tuned. The final power amplifier will operate at peak performance only
when its load is resistive – i.e. the SWR is close to 1.0. Therefore the PT-8000 is equipped with an
automatic antenna tuner (ATU) which does not actually tune the antenna. The ATU instead matches the
feedline to the final amplifiers so they always "see" and SWR of 1.0. The ATU has its limits – tuning
mismatches with SWR greater than 2.0 become difficult and will exceed the capabilities of the ATU.
Using a tuned or resonant antenna with 50 Ohm impedance at the feedpoint for the specific frequencies
is highly recommended. The purpose of the ATU is to ensure that a resonant antenna can be used at the
limits of the band selected with optimum performance of both PT-8000 and antenna system. Never try to
hook up a symmetrical open feeder line (balanced, twin-lead, ladder line etc,) directly to the PT-8000.
Instead use 50 ohm coaxial feeders only. The connectors supplied on the PT8000 are all Type N.
With the ATU it is acceptable to use a broadband antenna system like a log periodic or T2FD system
which trade wide bandwidth for an SWR ranging as high as 2.0.
Part B Installation
Picture 1
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