Commander VHF-1200 Six Meter Linear Amplifier 50-54 MHz

Description

Six Meters Specifications 50 - 54 MHz
Modes: all modes used in the amateur service
Power requirements: 117/200/234 VAC @20 amps
RF drive power: 15 - 25 watts nominal or 35 - 45 watts for maximum output
RF output: 1200 watts pep for SSB operation or 700 Watts continuous carrier (no time limit)
Input impedance: 50 ohms
Output impedance 50 ohms nominal
Antenna load: 2:1 VSWR max
Harmonic suppression: - 60db @ 1200 watts pep
Intermodulation distortion: -35 dB or better @ 1200 watts pep
Weight: 75 lbs.
Cabinet size: 8.75 x 18 x 16.5 in.
Tube compliment: 3cx800a7 Eimac ceramic metal triode
Pressurized chassis forced air cooling
Used only once each year during June VHF contests, like new condition.
FREE Local Pickup or Delivery
USA Shipping UPS Ground
Transformer & Tube will be removed and shipped in separate cartons.
Shipping will take a few days to pack & schedule.
Operates All Amateur Radio Modes
The Commander VHF-1200 is designed for top performance in any Amateur mode of operation.
Features
Reduced ratio (6 to 1) on all tuning controls for smooth and easy tune up
Dual front panel meters monitor grid current, plate current or plate voltage
Silver plated tank coil with Teflon support and a high Q piston tuning capacitor
Effective rear panel adjustable ALC
Grid over current trip out with 5 second reset
Hypersil plate transformer
Inrush current protection with solid state relay
Ge Lexan front panel surface
Rear panel adjustable tuned input ( l c l circuit)
Contemporary Styling With Ge Lexan Front Panel Surfac
e
The two tone gray colors with accents and nomenclature in contrasting black gives a clean and professional appearance. The GE Lexan front panel provides a tough surface that resists abrasion and wipes clean. All colors and graphics are printed behind the surface so they will last forever.
The Same Commitment To High Quality And Performance
The Commander VHF 1200 was designed and built for those discriminating operators who want the same high quality, performance and ruggedness that goes into every Commander amplifier.
High Power Output Effortlessly
If you like contesting on SSB or simply like to "rag chew" with fellow HAMS the Commander VHF-1200 delivers 1200 Watts PEP output effortlessly. You will be able to deliver a clear, clean, crisp, splatter-free signal. On CW the VHF-1200 delivers up t
o
1000 Watts output. For all high duty cycle modes you can operate at 700 watts output key down with no time limit.
Adjustable Rear Panel Drive Limiting (Alc)
The VHF -1200 has a rear panel adjustable automatic level control circuit that develops a negative voltage to control the output on most modern transmitters to prevent overdrive.
Fail Safe Tube And Power Supply Protection
Excessive grid current protection is provided with an automatic trip out that places the unit in stand-by if a preset grid current is exceeded. This circuit resets in approx. 2 seconds after the key line opens. Additional tube protection is provided by a fuse in the cathode circuit. A 50 ohm 50 watt resistor in the power supply B+ and a 10 watt 200 ohm resistor in the B- protect the high voltage components in the event of an arc or flash over.
Solid State Relay Provides Inrush Current Protection
Inrush protection is provided with the use of a solid state relay that senses the ac line phase angle and only activates at the sine wave zero crossover point.
Pressurized Chassis Forced Air Cooling
The Commander VHF-1200 utilizes full chassis pressurized forced air cooling. A Dayton 50 CFM blower (mounted in rubber) cools all components, including the high voltage supply. The blower is mounted on the opposite side of the chassis from the exhaust to prevent re-ingestion of hot air. A power resistor in the ac lead slows the speed slightly to allow for less noise.
Adjustable Rear Panel Tuned Input Circuit
We ship each amplifier with the tuned input circuit factory set for a "near perfect match" of 1:1 input between your transmitter and the amplifier. If you should find it necessary to make any adjustments, they can be easily and safely made thru access holes located on the rear panel.
State-Of-The-Art Power Supply
The power supply for the VHF-1200 is identical to the one used on our HF-2500. This power supply will deliver up to 2500 watts input power effortlessly. The primary has been conveniently tapped for 117-200-234 Vac. 50 or 60Hz operation.
The eight 270uf - 450 WVDC electrolytic filter capacitors have a total capacitance of 33.75uf. These filter caps are of the new polysyllabic type currently used in switching power supply technology. Their reduced size allows them to be placed inside the pressurized cooling airstream for long life.
Standard Tape-Wound Hypersil Power Transformer
The VHF-1200 utilizes a high quality and high performance tape-wound hypersil transformer, the same unit that we sell with our HF-2500 amplifier. Although this may be "overkill" it will deliver noise free operation at full output. In other words you will have to look at the meters to see the output as you will hear no complaint from your VHF-1200. Unlike most other manufacturers, all Commander amplifiers utilize separate filament and control voltage transformers. The main transformer supplies only the high voltage. This insures better power supply regulation which gives you better performance.
Why You Should Buy A Commander Amplifier
In a word, value. The Commander amplifiers combine quality, performance, and ruggedness in one powerful package. Their unique design, using only top quality materials, insures not only your operating enjoyment but your long term satisfaction. The loud and clear reports you will receive along with no complaints from operators on adjacent frequencies will make you one of those discriminating operators that others will admire.