SW BC amp

Home ] Up ]


3CX15000A7 amplifier 3-23 MHz. 25 kW SSB output.


Antenna transfer relay





















Antenna relays. Small relay on left (upside down) is an RJ-1 relay. Big relay is 30 amperes at 15 kV vacuum.



Amplifier tank circuit



Main inductor.

5/8th inch tubing.

Thick silver plate. Brazed connections.









Bandswitch 8 inches in diameter.

Coiled leads fine tune the inductance.








3CX15000A7 prior to plating




Silver plated lead






Not silver plated yet.


















Bias board











RF compartment.










3CX15000A7 power supply side




Left, air pressure differential cutout.

Turns amp off if air pressure across 3CX15000 anode goes below rating.

EIA flange RF output connector

Small 380-pound test power transformer with lift hooks. Replaced at site with bigger three-phase.















Large amp RF deck view






Left, RF choke.

3CX15000A7 tube.

Tank coil.

Normal 3 kW size RF amplifier plate choke is used for dc tank safety.








EIA output flange








Belt drive for tuned input system








Vacuum cap drives and belt drive for input.

All of the shafts and sheet metal are made here.














3cx15000A7 homebrew RF  plate choke



Homebrew RF plate choke. #14 wire.

Homebrew plate choke supports.




Blocking capacitor.
















3cx15000A7 control and power wiring




All homemade metal.


All welding done here.




















3cx15000A7 bias and control

























Power relays