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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300w 23cm Amplifier

Published in QST magazine (December 2004). Also see ARRL web files.

The 23 cm amplifier pictured here delivers more than 300 watts with 10 watts drive. I've actually driven it to 400w+. It's water-cooled, thermally stable, and very smooth-tuning. It includes a TR switch, relay sequencer, and all controls necessary to operate the amplifier safely and reliably.

click any of the thumbnails below for enlargements or explanations

The Completed Amplifier The Performance Test The modified GS-15B Tetrode Why Water Cooling?
completedamp.jpg (101140 bytes) pwrmeter.jpg (64616 bytes) thetube.jpg (6331 bytes) watercooler.jpg (26271 bytes)

At it's heart is a Russian tetrode, the GS-15B, modified for water cooling. It runs in a well-made cavity I purchased from Mats Bengtsson, KD5FZX.  Complete information on the cavity itself can be viewed here, courtesy of Mats and Paul Goble, ND2X.

Featured below are construction details on the complete amplifier and power supply I built for this cavity. Click here for the complete schematics.

Simplified Schematic Power Supply 101 +28 and +12 volt supplies Bias and Metering
simpleschematic.jpg (44314 bytes) ps-1.jpg (22066 bytes) lvps.jpg (24773 bytes)
Relay Sequencer Mounting the Cavity Coolant Connector Parts RF Relays
coolantparts.jpg (34495 bytes) relays.jpg (23228 bytes)
Some Other Parts PCB Mounting Cavity and 2nd Fan Mount Ventilation
meterswitch.jpg (26904 bytes) pcbmount.jpg (52393 bytes) cavandfan.jpg (49456 bytes) ventholes.jpg (51759 bytes)
RF Cabling PCB Wiring PCB Component Side Wiring View (top)
rfcables.jpg (35557 bytes)
Another Top View HV and Disconnects Other Disconnects Rear Panel Lettering
cavitydisconnects.jpg (73961 bytes) moredisconnects.jpg (56272 bytes) rearpanel.jpg (76696 bytes)
Power Supply Tuneup