Specifications

Alpha 9500 HF Linear Amplifier Operating Manual Alpha Radio Products
Maintaining and Upgrading the Amplifier Product Release 1
DOCNUMBER 9500
Document Issue 1, Revision 7
Page 8–4 June 2009
88
8
!
IMPORTANT The amplifier is equipped with a cover interlock switch that removes
primary power from the amplifier, and a crowbar that short-circuits
high voltage to the chassis when the cover is lifted. These interlocks
protect against electric shock resulting from accidental contact with
the lethal voltages inside the amplifier.
Do not disable the interlock switches for any reason.
Procedure 8-3 Replace the tube and fuses
Step 3 Replace the tube.
The amplifier uses a single CPI Eimac Corporation 8877 (3CX1500A7)
ceramic triode tube.
Step 4 Replace fuses.
USE ONLY 20-A, 250-V-RATED FUSES for 190–220 VAC service.
You may use 25-A fuses with caution for line voltages of 90–130 V.
Never replace a fuse with one of a different type or greater current rating.
Blowing of one or both primary line fuses indicates that the maximum
safe average power capability of the amplifier has been substantially
exceeded or that an equipment failure has occurred.
The slow-blow fuse F3, located below the primary line fuses, may prevent
damage to the step-start resistors and HV rectifiers in the event of
abnormal turn-on conditions or HV faults. If the AC interlock is defeated
and primary power is applied while the HV crowbar is closed, the step-
start fuses normally blow.
!
IMPORTANT Damage resulting from use of a fuse of incorrect size or type is not
covered under and may void the warranty.
Step 5 Replace the cover and reconnect the AC line cord to the power source.
8.4 Upgrade Firmware
Occasionally, new firmware for the ALPHA 9500 control board becomes
available for download from the Alpha website.
Go to the Alpha website, retrieve the firmware, and store it on your PC.
Then choose one of the following procedures and follow it to install
firmware.