2
DOCNUMBER 8410
Document Issue 1.1
August 2015
Page 2–1
2
Amplifier Components and Specifications
2.1 Boards 2–3
2.2 Controls and Display 2–6
2.3 Output-Tank Circuit 2–6
2.4 Tubes and Tube Deck 2–6
2.5 Specifications 2–7
Remember
REMEMBER
Amplifier components as photographed for this manual may differ
from those in your amplifier, depending on your amplifier vintage.
The Alpha 8410 uses ceramic-and-metal forced-air-cooled tetrode
vacuum tubes for amplification. The main power supply is an unregulated
transformer/rectifier/capacitor power supply for the high-voltage (HV)
and heater circuits. All other power supplies are regulated.
The control circuit uses a microprocessor “in the loop” to monitor and
control amplifier operation. There are seven circuit boards in the
amplifier:
•
Center-partition board
•
Control board
•
Display board
•
HV board
•
Mains board
•
Transmit/receive (T/R) board
•
Tube-deck board
In addition to these, the tubes, tank circuit assembly, and transformer
complete the main sections of the amplifier. These major blocks are
described below.
The amplifier includes a 5-V power supply mounted behind the front
panel. Whenever the amplifier is plugged into the mains power, this
supply is active and there is power to the microcontroller on the main
control board. This feature enables the amplifier to be turned on or off
remotely. It also enables remote monitoring and debugging via a USB
cable connected to a computer.
