AMPLIFIERS by
www.amplady.com
EMTRON DX-1b
GENERAL
DESCRIPTION
Due to
its small size. light weight and a very much over-rated cooling system, the
DX-1b is not only suitable where a small
footprint is required, it is also ideal for DXpeditions. Delivering a solid 800
watts continuous output power without time limit, we consider the DX-1b the very
best in the world in its class.

SPECIFICATIONS
Band
Coverage
The
Emtron DX-1b covers all nine amateur bands from 160 thru 10 meters including
WARC bands at full power.
It utilizes a ceramic high quality 9-position band switch for each amateur band.
No band compromises like on many other amplifiers on the market.
Modes of
Operation
The
Emtron DX-1b has been designed and built to operate in any mode such as: SSB,
CW, AM, FM, RTTY and SSTV and with optional QSK Module all current digital
modes.
Output Power
In
order to achieve full power output of 800 watts continuous carrier, an input
power approximately 40 to 60 watts is required. If your delivers more output
power, reduce the drive level.
Specially when
operating RTTY or any other continuous mode, reduce the drive level and let your
transceiver run "COOL" with less strain on its output components. In
cases where the drive is too high, the DX-1b will let you know of the overdrive
condition by automatically bypassing itself for 2 seconds. This action will be
repeated until the drive power is reduced.
The Emtron DX-1b is comfortable with all popular transceivers such as Kenwood,
ICOM, Yaesu, JRC, TenTec, etc.
Tube
The
Emtron DX-1b operates with one 4CX800A/GU-7B tube, in Class AB1 with a plate
dissipation of 800 watts. Constructed primarily for military communication, this
tube is physically and electrically exceptional rugged and with additional
sophisticated protection circuitry incorporated, the DX-1b is almost indestructible. The
4CX800A/GU-7B tube is a compact high slope
(35mA/V tetrode) and when operated under normal conditions, will last a very
long time.
Tube
Protection
The Emtron DX-1b has a very sophisticated tube protection circuitry, designed to
protect excessive plate current, screen grid current, screen grid voltage, bias
voltage, overdrive, SWR, etc. The tube is also protected from excessive
temperature by continuously monitoring the required airflow temperature. In case
of any fault, the amplifier is automatically cut off. A 25 ohm, 50 watt resistor
in the B+ circuit and a MOV in the screen circuit further protects the tube and
the power supply from a possible tube internal flash-over.
Cooling
A lot of attention was given to the design of the DX-1b's cooling system. A
pressurized forced air cooling to achieve with a rugged temperature controlled
2-speed 70 CFM blower (turbine) which effectively cools all critical components
of the amplifier. The volume of cooling air far exceeds manufacturers'
specifications for all critical components. The blower is positioned in such a
way that it prevents hot air being circulated through the system.
Automatic
Drive Level Circuit(ALC)
The ALC circuit in EMTRON DX-1b amplifier is not of a conventional design like
in all other amplifiers. The DX-1b's ALC Circuit operates only for one reason -
to prevent overdrive and keep the signal clean. While operating the DX-1b, you
could never get the WAN (Worked All Neighbors) AWARD!! No wonder, the nice
compliments the DX-1b operators get on the quality of their signals. The ALC in
DX-1b senses any slight overdrive (50 micro-amps of grid current), warns you,
and if you don't do anything about it, will cut you off for 2 seconds. The 2
second cut-off is then repeated until the drive level is reduced. This ALC
circuit also produces a 1V - 10V negative going voltage, proportional to the
grid current, but only when overdrive is present. The EMTRON DX-1b can be
operated without connecting your transceiver to the ALC output of the DX-1b and
you are still guaranteed never to overdrive it. However, connecting the ALC will
prevent the overdrive condition to occur in the first place, and you will not be
cut off.

Power Supply
The
power supply of the EMTRON DX-1b is also unique. It contains a "SOFT
START INRUSH PROTECTION",
a top grade heavy duty transformer, a full bridge rectifier and eight high
voltage filter capacitors of 470 uF/500 volt rating. This gives a total
capacitance in the high voltage section of 58uF and a voltage rating of 3600
volts. The soft start inrush protection circuit in the new DX-1b
amplifier is another unique design found in no other amplifier so far. It is the
best soft start system available today. The phase controlled 20amp TRIAC
will turn on the amplifier using a 3-second ramp function. The electrolytic
capacitors are charged linearly over the 3 second period. This also affects all
other circuit components in a similar manner. Stress in components, failure and
"TRANSFORMER BONG" are non-existent in the EMTRON DX-1b. Yet another
unique new design, exclusive to the EMTRON DX-1b amplifier is its screen grid
power supply. Fully voltage regulated for +ve and -ve screen currents, combined
with very effective current limiting, not only totally protects the GU-74B tube,
but also due to its wide dynamic range, it keeps the tube static operation
parameters absolutely stable. The protection against excessive screen current is
so good, that we have tested the operation with full screen voltage, while the
plate voltage was absent, for extended time, without damage to the tube.
Needless to say that there is quite a lot of sophisticated electronics present
in the DX-1b.

Display
All important parameters such as plate current Ip, plate voltage Ep, output
power, reflected power, screen grid current, SWR, overdrive, ready, transmit and
fault information is displayed on a simple solid state display panel utilizing
LED of different colors and two large analog meters. No switching of any
parameter except Vp, Po and Pr is required. This unique combination of analog
moving coil meters and solid state LED display panel gives you the best of both
worlds. When tuning the amplifier, the three most important parameters, Ip, Ig ,
and Po are displayed at the same time.

Components
Only the very best components with no compromise are used in EMTRON DX-1b
amplifier. All RF components such as band switch, tank coils, chokes, etc. are
of high quality silver plating, ceramic bobbin for lower frequencies is also
used.
Finish
The finish is of high quality durable baked enamel texture paint and silk
screening of a quality not found on any other similar equipment.
Warranty
FOUR YEARS full warranty covers all parts and labor, and limited warranty on
tube
FACTORY DIRECT SALES
AND SERVICE via www.amplady.com
The EMTRON DX-1b is sold factory direct; no "middle man" mark up, you
do business with the designers and producers, with people who know the heart of
the DX-1b, and they will always be able to give you any technical advice.
So get the biggest bargain in top brand linear amplifiers. Emtron DX-1b is the most technically advanced RF linear amplifier operating on all HF amateur radio bands, developed with quality, reliability, performance and price in mind.
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