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The
dual XRF-286 amplifier pictured here makes use of many of the components from
the other technical articles featured on this site.
An excellent match for those of us with a 10w driver (like the IC-910, TS-2000X, 736R, TS-790, small transverters, etc.), it will produce 150 watts output, all modes. It has a built-in sequencer and low-loss Dow-Key antenna transfer switch.
Designed for home station use, it's compact internal switching power supply runs on standard AC power, selectable for 120v or 230v, 50-60 Hz.
A high-VSWR sensor will lock out and bypass the amplifier
if it senses a load VSWR greater that 2/1 (internally adjustable). It will
remain locked out until reset (a reset is performed by powering off the amplifier for a few seconds).
The rear panel has a clean layout, with connections for the driver, antenna, key-line from the driver (PTT), and AC power.
Cooling air is drawn from vents in the cabinet floor, and warm
air expelled out the rear vent.
Viewing the left side of the cabinet with the cover removed shows the AC line fuse and the fully bypassed AC connector module (left rear), the control board (center), and the 150w amplifier itself (top center).
On the front panel (right) are the indicator LED's, switches and panel meter.
Shown at the bottom, and underneath the amplifier heat sink,
is the 28v power supply.
Behind the front panel, and mounted to the rear of the heat sink, is the cooling fan, positioned to cool both the power supply and the amplifier assembly.
There are two wiring interconnects (far left); should
the amplifier ever require servicing, the front panel can be unplugged and
removed for easy access to everything else.
On the right side, the slide switch for 120v or 230v operation is readily accessible (just beneath the yellow label).
This photo also shows the Dow-Key antenna transfer switch, the RF shielding around the panel meter,
and the bulkhead N connector transitions into the rear panel..
This photo displays the amplifier deck; the small brown board at the output of the amplifier is the SWR coupler/detector board.
Also visible here is the FET switch (the small green board at upper right), which connects 28v to the amplifier during transmit.
The small board at the bottom center is the temperature sensor
for the fan controller.