Furuno FAR-3220Z, Руководство по установке

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2. WIRING
2-5
2.3.2 How to connect the power cable
1. Remove the connector cover for the power cable.
2. Fabricate the power cable (TPY-1.5) as shown below.
3. Pull up the plastic cover and connect the power cable.
4. Remount the cover.
5. Reattach the cover of the power supply unit.
2.3.3 How to connect the flexible waveguide (FR-9)
The RF interconnection between the antenna unit and the transceiver can be made
with a flexible waveguide (FR-9). If the rectangular waveguide is used, observe the fol-
lowing installation guidelines.
• Correctly installed waveguide runs ensure the most efficient transmission of electri-
cal energy at high frequencies. Electrical losses, however, occur in the waveguide
runs. To minimize them the following factors are of great importance: minimum
length, airtightness and electrical continuity.
• Another consideration required is that of frequency disturbance. The transmitting
valve, a magnetron, is the primary oscillator in the radar. This is different from the
oscillation system at lower frequencies in which conventional radio valves are used.
In the latter case, the primary oscillator is always protected from the effects of load
impedance by a buffer stage so that frequency and waveform are left unobstructed.
With a waveguide and magnetron, however, mismatch of impedance causes “fre-
quency pulling.” For this reason, the number of possible mismatches in a waveguide
run, i.e., joins and bends, must be kept minimum.
• Each pair of flanges should be coupled with one O-ring, four bolts and spring wash-
ers and the choke flange must be in the upper position. The bolts and O-ring must
be greased before insertion to facilitate removal if required at a later date.
FG
Connector cover
Sheath (clamp here.)
Crimp-on lug
(FV2-M4)