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
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
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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100w 23cm "brick"

I built this 4-module 100w amplifier assembly to be used as a component in a high-power portable transverter, intending to use it in a rover setup for contesting. Here's some background info on the individual amplifier boards and couplers.

Only 500mw drive is needed for 100w out...300mw would be enough if the on-board input pads are left out; maximum output is 120w (saturated).

In this picture, you are seeing only the left two of the four 30w amplifier boards, with the main input hybrid splitter/coupler and output hybrid combiner/coupler mounted to the top plate. These components combine each of the two 60w sides.

In the next technical article, I put this inside a transverter cabinet in it's own compartment (construction similar to the 9cm transverter), complete with a quiet muffin fan moving air through the fin cluster in the center.

I attempted to make the heat sink as physically small as possible, yet still be capable of dissipating the heat properly.

To do this, I used two smaller pieces of heat sink, each large enough for a 60w amplifier pair to occupy.

I made up a couple of binding plates using .060 aluminum sheet, and put the two halves together as show here, before the other components were mounted.

Putting the fins together like this allows air to be directed easily into the fin cluster, exhausting at the rear of the assembly.
Here's a look at one end of the fully assembled unit.

I wound up making the mounting plates a bit wider than you saw in the previous photo; this allows the top couplers and the components on the sides to have some clearance and mechanical protection.

The whole thing is still very compact at 4"W x 4.5"H x 8"L