All band, All mode coverage

The AL-811 covers all HF bands. Theres no compromise on WARC and most MARS bands -- you get 100% rated output. You can operate the AL-811 on all modes. Get 600 watts output PEP SSB and 500 watts output CW. You even get 400 watts on demanding continuous modes like RTTY, SSTV, FM and AM.

How the low cost 811A tube resists premature failure -- even when your amplifier is mistuned

First theyre constructed with widely spaced elements that minimize the chance of touching and causing a short -- even if the plate gets hot enough to melt. Second they use a directly heated thoriated tungsten filament cathode that prevents the electron emitting layer from instantly stripping off -- even if mistuning causes a sudden, sever current overload. The Ameritron AL-811 is excellent for the newcomer because its tough enough to withstand momentary mistuning. And the tubes are so inexpensive that you can replace one for mere pocket change.

The Ameritron advantage: Extra heavy duty power supply gives you peak performance year after year
The heart of the AL-811 power supply is its heavy duty power transformer with high silicon steel core weighing a hefty 17 pounds. A full wave bridge using 52.5 ufd of total capacitance (four 210 ufd, 470 volt capacitors) produces 1500 volts under full load and 1700 volts no load. Thats excellent high voltage regulation! Full height computer grade filter capacitors with screw terminals are used -- not short stubby. light duty soldered-in "high technology" capacitors that cant dissipate the heat generated by high current.
Rectifier diodes are rated for a massive surgecurrent of 200 amps. They wont blow even if you accidentally short the high voltage supply. Wire wound, 7 watt, 50 K ohm equalizing resistors safely protect each filter capacitor -- not 2 watt, 100 K ohm carbon composition resistors that can open and cause your filter capacitors to explode or fail. The Ameritron AL-811 power supply is built tough so you get peak performance year after year.

Tuned input provides excellent load for any rig

A Pi-Network tuned input provides a 50 ohm load for your rig. Even fussy solid state rigs can deliver their full drive to AL-811. Low loss slug tuned coils -- tunable from the rear panel -- let you optimize performance. High quality low drift silver mica capacitors maintain proper tuning.

Output tank: optimum Q on each band

the low loss pi-network output tank of the AL-811 has been carefully designated for optimum Q on each band and built with quality RF components. The result is peak performance over each band, wide impedance matching range and exceptionally smooth tuning with efficiencies close to 70%. Even a 3:1 SWR load wont damage the tubes or tank components. A ball bearing vernier reduction drive makes plate tuning precise and easy.

Quiet pressurized ventilation keeps your tubes safely cooled

A quiet blower pressurizes the cabinet with a large volume of air flow. It keeps the 811A tube temperature well below the tube manufacturers rating -- even with a key down carrier at 400 watts output -- without the overwhelming noise of oversized fans.

Two illuminated meters

Two illuminated meters give you a clear picture of your AL-811 operating conditions so you can tell right away if something is wrong. the Grid Current meter continuously check for improper loading. The other meter switches between high voltage and plate current to warn of abnormal conditions.

Ameritron exclusive Adapt-A-Volt power transformer

Too high line voltage stresses components and causes them to wear out and fail. Too low line voltage causes a "soft-tube" effect -- low output and signal distortion. Ameritrons exclusive Adapt-A-Volt power transformer has a special buck-boost winding that lets you compensate for stressful high line voltage and performance robbing low line voltage. This makes your components last longer and gives you peak performance -- regardless of your line voltage.

QSK Compatible

For lightning fast QSK operation, use the optional external QSK-5, electronic PIN diode switch.

Plus More...

An Operate/Standyby switch lets you run barefoot, but you can instantly switch to full power if needed.

A transmit LED tells you when your rig is keying your AL-811.

A 12 VDC keying relay makes it compatible with solid state and tube rigs. Built-in back-pulse canceling diode protects your rigs keying circuit.

Shielded RF compartment. One year limited warranty. UPS shippable. Shipped with transformer installed and wired for 120 VAC. Draws 8 amps at 120 VAC.