Hallicrafters HA-1, Operating And Service Instructions

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SECTION VII
SERVICE DATA
7-1. CHASSIS REMOVAL
The chassis and front panel assembly can be easily withdraw from the
cabinet after the four screws on the bottom of the cabinet have been removed.
7-2. TUBE AND NEON LAMP REPLACEMENT
Complete access to all tubes can be obtained b removing the chassis from
the cabinet (see paragraph 7-1). The neon lamp is accessible from the front of the
cabinet.
7-3. TROUBLESHOOTING
Throughout the design of the Model HA-1 keying unit, full consideration was
given to keep maintenance problems at an absolute minimum. However, if a
malfunction does occur, the voltage chart and schematic diagram will aid in
isolating and correcting the malfunction. For the physical location of component
parts, refer to figures 7 and 8.
NOTE
The mercury-wetted relay will operate if inclined 30° or more
from the horizontal plane.
7-4. Model HA-1 TUBE SOCKET VOLTAGES
Tube 1 2 3 4 5 6 7 8 9
V1
V2
V3
V4
V5
V6 115
1
12
150
150
GND
120
–17
0
–15
N.C.
N.C.
120
GND
GND
GND
N.C.
N.C.
GND
GND
GND
GND
N.C.
N.C,
H
H
H
H
N.C.
N.C.
21
120
105
150
N.C.
N.C.
0
–10
–12
0
GND
–108
GND
GND
1
4
- -
- -
N.C.
N.C.
N.C.
N.C.
- -
- -
NOTES:
1. Measurements were made with a vacuum tube voltmeter connected
between indicated tube socket terminal and chassis.
2. Measurements were made with the FUNCTION switch in the LOW po-
sition; SPEED control maximum clockwise; BALANCE and WEIGHT