Specifications

2 TECHNICAL SPECIFICATIONS

FREQUENCY COVERAGE: Complete (manually tuned) coverage of the nine HF amateur bands:

1.800 – 1.900 MHz

3.500 – 4.000 MHz

7.000 – 7.500 MHz

10.000 – 10.300 MHz

14.000 – 14.350 MHz

18.000 – 18.500 MHz

21.000 – 21.500 MHz

24.000 – 24.500 MHz

28.500 – 29.990 MHz

TRANSMITTING MODES: Both continuous and low duty cycle modes are supported. That is, the DX-3

supports SSB, CW, AM, FM, RTTY and SSTV. II

OUTPUT POWER: Typical 3000 watts carrier or up to 4000 W PEP

DRIVE POWER: Nominal 60-90 watts for full rated output.

INPUT IMPEDANCE: Nominal 50 ohm passive impedance, unbalanced. VSWR 1.4:1 or less.

OUTPUT IMPEDANCE: Nominal 50 ohm passive impedance, unbalanced. VSWR 2.6:1 or less.

DISTORTION: Third order intermodulation products are more than 35 dB below rated output.

HARMONICS: Harmonic output is better than 50dB below the rated output.

FAULT PROTECTION: The comprehensive fault protection system include circuitry to monitor:

• plate current: should the plate current exceed a safe value, the amplifier goes to standby mode for 2

minutes.

• screen grid over-current: Absolute tube protection is offered with visual warning and a reduced power

level being enabled if the screen current exceeds a pre-set limit.

• temperature: Should the tube's temperature exceed a specific level, amplifier operation is suspended

until the temperature drops to a safe level.

• Flash-over: a 3-stage protection circuit using extremely fast MOV’s protects the screen regulator from

the dangerous plate voltage in case of a flash-over in the tube.

OPERATIONAL PROTECTION

• Overdrive protection: Should the DX-3 be overdriven, a LED warning indictor will light up when the

linearity limit is reached. If the drive is increased further, a 2 second cut off (by-pass) will follow.

• SWR protection: Should the DX-3 sense an SWR exceeding 2.6:1, a LED warning indicator will light

up, simultaneously with a 3 second cut off.

METERING: The front panel moving LED display systems indicate:

“Moving light” LED indicators:

• output power

• reflected power

• screen grid current

• plate voltage

• plate current