High power amplifier for 1296
1 KW SSPA for 1.8-54 MHz
A 1.5 KW LPF for 160-6m
1.8 to 54 MHz Dual Directional Detector
1.8 to 54 MHz combiner set
Automatic Transverter Interface
1 KW 6 Meter LDMOS Amplifier
2 Meter 80W All Mode Amplifier
1 KW 2M LDMOS Amplifier
1 KW 222 MHz LDMOS Amplifier
500w 70cm Amplifier
1KW 70cm LDMOS Amplifier
A Big Power Supply for SSPAs
Low Pass Filter/Dual Directional Detector
Sampling RF Power
LED Bar Graph Meter
Amplifier Control Board
LNAs (preamps) and MMICs
LNA Sequencing and Protection
Building UHF Antennas
MIcrowave Marker
Crystal Oven Controller
Microwave L.O.
Latching Relay Driver
12 to 28v
Relay Sequencer
High Current DC Switch
L & S Band LNA
Microwave L.O. Filters
PC Board Filters
Using Inexpensive Relays
600w 23cm LDMOS Amplifier
XRF-286 Amplifiers for 23cm
150W 23CM Turn-Key Amplifier
300w 23cm Amplifier
200w 23cm Amplifier
100w 23cm "brick"
100w 23cm Transverter
60w 23 cm Amplifier
23 CM Beacon
23cm Signal Generator
23cm Double Quad
23cm filters
13cm filter
13cm Signal Generator
13cm Transverter
120w 13 cm Amplifier
600w+ 33cm Amplifier
300w 33cm Amplifier
33cm filter
33 cm Crystal Source
33cm Signal Generator
9cm Transverter
Transverter Selector
12 AND 28 volts
Klitzing Amplifiers
IC-910H tweaks
Audio Files
Parts I Can Supply
Current Projects

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150W 23CM Turn-Key Amplifier

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.