ND
200S/D 
NAUTEL's ND 200 S 50 Watt NDB has been developed for use
as a highly reliable, highly efficient transmitter. It may used
either as an aeronautical or non-sequenced marine locator NDB.
The 50 Watt output is fed via a 50 ohm coaxial feeder either
directly to a suitable automatically tuned Polestar series
antenna or via a separate Automatic Antenna Tuning Unit, Model NX
500 TUB, to the customer's existing antenna system.
Specifications :
Power : 50 Watts continuously adjustable down to 25 watts.
Freq. range : 190 to 535 KHz.
Freq. stability : ±0.005% or better over full environtmental range.
Modulation Level : Adjustable from 10 to 95 %.
Emmision modes : NON (CW); A2A (MCW Keyed Tone).
Internal keyed tone frequency : 400 or 1020 Hz ± 5%.
Keying : Solid State programmable keyer, 1, 2 or 3 letters of Morse Code at 7 words/min, 48 or 64 bit code cycle.
Harmonic levels : Not exceeding -60dB relative to the carrier into a 50 ohm load.
Hum and noise : Not exceeding -46dB relative to 95% modulation level.
Audio distortion : Total audio frequency distortion not exceeding 5%.
Metering : FWD/REFL Power; % Modulation; Unregulated voltage; Regulated voltage; Tone level; DC Current; RF Drive.
Transmitter shutdown threshold : Transmitter shutdown will occur if : a. Carrier power reduces more than 3dB; b. Modulation or keying fails.
Power requirements : 120/240V AC Single Phase 50/60 Hz, 160 VA max. Standby power 48V at 2.5 amps.
Environmental limits : -10°C to +70°C ; 0 to 95% relative humidity (ventilated cabinet).
Climate : Any - including tropical.
Dimensions (HxWxD) : 61x30.5x30.5cm (24x12x12in).
Weight : Unpacked - 41 kg (90lbs); Packed - 44kg (98lbs).
Option : 001. Weatherproof cabinet. Revised environmental limits = -10°C to +55°C, 0 to 100% relative humidity; 002. Automatic changeover to standby transmitter (required for dual ND 200 installation); 003. NX 500TUB (equivalent to FA9782/1) Automatic Antenna Tuning Unit for use with other than Polestar Antennas; 004. 48V 3 AMP Lead Acid or NICAD Battery Charger; 005. Simultaneous A3E (voice Modulation).
PA 60A (60 foot); PA
40A (40 foot)
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POLSTAR PA 60A and PA 40A Series antennas is
designed to provide a complete antenna-tuning-matching package to
interface directly at a 50 ohm (coaxial) impedance level with
medium powered transmitters in the LF and MF bands They are
intended particularly for use with aeronautical and marine
radiobeacons (NDBs) but may also be used to advantage for MF
Telegraphy and AM Broadcasting.
Specifications :
Electrical :
Frequency range : 190 - 535 KHz (custom designed for actual operating frequency in this range).
Input RF power rating : Up to 125 Watts carrier; 500 Watts peak.
Input impedance : 50 ohms at VSWR less than 1.25 : 1.
Top section capacity : 200 picofarads (approx.).
Loading coil quality factor (Q) : 250 - 350.
Motorized auto-adjustment : ± 2.5 % (min) of total loading inductance.
Radiation pattern : Omnidirectional.
Tuning Motor : + 12 Volts dc.
Mechanical :
Installed height : Tower height + 0.9m (3.0 ft) (approximately)
Packed Weight : 136kg (300lb) + 11.8kg/m (8.0lb/foot) for tower and hardware (approximately).
Ground Plane : Radial network of 6 wires, each 50.3 m (165 ft) long.
Tower : Guyed aluminum lattice - 38cm (15 in,) triangular cross section.
Radiator : High strength aluminum alloy.
Environmental Limits : -50°C to + 55°C.
NX
500TUB 
NAUTEL Automatic Antenna Tuning Units eliminates the
detuning problems inherent in high 'Q' LF/MF antennas encountered
under varying climate conditions. A closed loop servo tuning
system ensures that the antenna is maintained at series resonance
and therefore provides a constant 50 ohm resistive load. This
allows the transmitter to be installed at any distance from the
antenna site.
Specifications :
Maximum carrier power : 125 watts.
Maximum P.E.P. : 500 watts.
Frequency range : 190 - 420 KHz.
Automatic tuning range : ± 5% Antenna capacity variation.
Input impedance : 50 ojms (VSWR < 1.25 : 1 at carrier frequency).
Power requirements : 15 VDC at 0.5 A max. Supplied from ND500.
Metering : FWD/REFL power and Antenna Current 0 - 10 and 0 - 2 amps.
Matching range antenna system resistance : 2 - 30 ohms.
Antenna capacitance* : 250 - 1000 pf.
Environmental Limits : -50°C to + 55°C, 0 to 100% relative humidity.
Climate : Any - including tropical.
Maximum series loss resistance of loading coil : Not greater than 1/200 x antenna reactance.
Size : Height 65.5cm (26.2"); Width 46cm (18.4"); Depth 25.5cm (10.2").
Mounting : 4 20.6mm (13/16") mounting holes for rear mounting. Vertical spacing 44.5cm (17.5"). Horizontal spacing 56cm (22").
Weight : 18 kg (40 lbs); 39 kg (86 lbs) packed.
* Lower limits :
i.e. minimum antenna capacity shown is for 190 KHz operation and defines peak voltage limit, lower antenna capacities can be accommodated at higher frequencies - consult factory for additional details.
Specifications are subject to change without prior notice.