HPE 606A Operating And Servicing Manual page 22

Sect. IV Page 2
Check tubes by substitution rather than using a
"tube checker'', The results obtained from the
"'tube checker'? can be misleading. Before re-
moving a tube, mark it so that if the tube is good
it can be returned to the same socket. Replace
only those tubes proved to be weak or defective.
TABLE 4-1.
Model 606A
Any tube with corresponding standard EIA charac-
teristics can be used as replacement. Where vari-
ations in tube characteristics will affect circuit
performance an adjustment is provided. Table 4-1
lists the tests to make and the adjustments that
may be necessary if such tubes are replaced.
TUBE REPLACEMENT
Circuit Ref. Tube Type and Function
Tests and/or Adjustments
V1 6AW8 Oscillator Level Control
v2 12AT7 RF Oscillator
V3, 4 6CL6 RF Amplifier
Beat Frequency Output
v10 6AW8 Crystal Oscillator and
Mixer
V101,2,3,4,5 12B4A Regulators
V106 6AW8 Amplifier
v107 12B4A Regulator
Vv108 6AW8 Amplifier
v109 5651 Voltage Reference
VS 12AT7 Audio Oscillator
V6 12B4 Modulator
v7 12AT7 Cathode Follower
V8 6AW8 Differential Amplifier
v9 12AT7 Modulation Monitor and
Set Maximum Oscillator Current;
par. 4-15
Set Maximum Oscillator Current;
par. 4-15
Carrier Zero Set; par. 4-16
Maximum Carrier Set; par. 4-17
RF Output Meter; par, 4-19
Audio Oscillator; par. 4-12
Mod. Zero Set; par. 4-17
Modulation Meter; par. 4-18
Maximum Carrier Set; par. 4-17
Mod, Zero Set; par. 4-17
RF Output Meter; par. 4-19
Modulation Meter; par. 4-18
Carrier Zero Set; par. 4-16
Maximum Carrier Set; par. 4-17
Mod, Zero Set; par. 4-17
RF Output Meter; par. 4-19
Modulation Meter; par. 4-18
Carrier Zero Set; par. 4-16
Maximum Carrier Set; par. 4-17
Mod, Zero Set; par. 4-17
RF Output Meter; par. 4-19
Modulation Meter; par. 4-18
Mod, Zero Set; par. 4-17
Modulation Meter; par. 4-18
Crystal Calibrator; par. 4-13
Crystal Oscillator; par. 4-13
Power Supplies; par. 4-11
Power Supplies; par. 4-11
Power Supplies; par. 4-11
Power Supplies; par. 4-11
Power Supplies; par. 4-11