AMERITRON AL-82 Gebrauchsanweisung - Seite 9

Blättern Sie online oder laden Sie pdf Gebrauchsanweisung für Verstärken AMERITRON AL-82 herunter. AMERITRON AL-82 16 Seiten. Full power
Auch für AMERITRON AL-82: Gebrauchsanweisung (16 seiten)

Seite drucken

LOCATION

Do not operate the Amplifier in excessively warm locations

or near heating vents or radiators. Be sure air can circulate

freely around and through the Amplifier cabinet. Provide an

unobstructed air inlet for the blower. Do NOT place anything

that will impede the free flow of air within 2 inches of the

cabinet ventilation holes.

VENTILATION

The AL-82 ventilation system has been designed and tested

to maintain tube seal temperature safely below the tube

manufacturer's rating at 1500 watts output with a 100% duty

cycle when properly tuned. The blower in the AL-82 is a

permanently lubricated type that requires no maintainence in

normal operation. To insure proper ventilation in your in-

stallation, observe the following:

Do not block or unduly restrict the ventilation holes in the

cover. Be sure that the amplifier

the vent holes have open air circulation.

2. The exhaust air flow is over 30 CFM. Do not "assist" the

air flow unless the fan exceeds the AL-82 blower CFM

by a factor of 2:1.

3. Do not mount additional fans on the AL-82 cabinet.

4. The exhaust air

become quite warm at higher power

will

levels. Do not place any heat sensitive objects in the

exhaust air stream.

Proper tuning of a grounded grid linear amplifier is best

accomplished with an understanding of what each control

does and v.hat the meters are telling the operator about the

condition of TUNE.

The tuning controls function as follows:

PLATE: This control tunes the amplifier output circuit to the

operating frequency. It should always be adjusted for

maximum output power or maximum grid current. Due to

interaction with the "LOAD" control, a "touch-up'' should be

performed after any load adjustments.

LOAD: This control adjusts the coupling of amplifier to the

antenna or load. It should be adjusted to keep the grid current

in the proper operating range. As the loading capacitance is

reduced (by rotating the control to a higher front panel

number), the coupling is increased. An increase in coupling

will reduce grid current and increase the amount of drive the

amplifier will accept without component damage.

A common mistake in tuning is to adjust the "LOAD" control

at low drive powers and apply more drive dur

INSTALLATION Cont.

located in an area so

Before you use a water pipe ground, inspect the connections

around the water meter and make sure that no plastic or rubber

hose connections are used. These connections interrupt

electrical continuity to the water supply line. Install a jumper

around any insulating water connections you may find. Use

heavy copper wire and pipe clamps. It is best to ground all

equipment to one point at the operating position and then

ground this point as described above.

TUNING INSTRUCTIONS

It is important to remember the loading must be set properly

for the PEAK power the amplifier is expected to develop. 50

watts PEP will be the maximum drive the amplifier will safely

handle if the output of the amplifier is tuned with 50 watts of

carrier drive. Any attempt to go beyond the amount of drive

power the amplifier was originally tuned at will result in a

rapid increase in grid current, splatter and even damage to

components.

The "LOAD" control should be adjusted for maximum output

power without exceeding the recommended grid current. DO

NOT USE THE LOAD CONTROL TO REDUCE POWER

IN A GROUNDED GRID AMPLIFIER. The drive from the

exciter should be reduced if the amplifier plate current or

output power is excessive. The "LOAD" setting should be

increased if grid current is excessive. Any errors in adjusting

this control should be made in favor of a higher load setting

(clockwise).

POWER CONNECTIONS

The AL-82 is supplied with a NEMA 6-15P plug for 240V

AC operation. Operation with power main voltages below 200

volt is not 'recommended. A special transformer is required

for 200\/, 50/60 Hz operation (see NOTE on page 1). Refer to

the "Transformer Installation" section on pages 4 and 5 for the

correct wiring for 220 to 240 volt operation.

NEVER REWIRE THE POWER SUPPLY TO BOOST THE

HIGH VOLTAGE ABOVE 3700 VOLTS.

The wiring between the fuse box and the amplifier AC outlet

must be No. 12 gauge or larger in order to supply the current

required (13 amperes) without a significant drop in the line

voltage. The outlet should be fused for 20 amperes.

GROUNDING

Connect a good RF and earth or water pipe ground to the

ground post on the rear panel of the Amplifier. Use the

heaviest and shortest connection possible.

ing operation. Excessive grid current, distortion on SSB or

arcing in the tank components occurs when full drive power is

applied to the amplifier without the "LOAD" set far enough

clockwise (higher loading).