TUBE: 6550
FICHIER SOURCE: sheets/049/6/6550.pdf
FABRICANT: RCA (Radio Corporation of America, Electron Tube Division, Harrison, N.J.)
ANNÉE: 1962 (5-62)
TYPE: Beam Power Tube (beam tetrode)

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6550 BEAM POWER TUBE
GENERAL DATA
Electrical:
Heater (Design-Center Values):
  Voltage (AC or DC) ... 6.3 ± 0.6 volts
  Current at heater volts = 6.3 ... 1.600 amp
  Peak heater-cathode voltage:
    Heater negative w.r.t. cathode ... 300(a) max. volts
    Heater positive w.r.t. cathode ... 200(b) max. volts
Direct Interelectrode Capacitances (Approx.)(c):
  Grid No.1 to plate ... 0.85 µµf
  Grid No.1 to cathode & grid No.3, grid No.2, base sleeve, and heater ... 14.0 µµf
  Plate to cathode & grid No.3, grid No.2, base sleeve, and heater ... 12.0 µµf

Characteristics, Class A1 Amplifier (Triode Connection(d)):
Plate Voltage ... 250 / 450 / 400 volts
Grid-No.2 Voltage ... 250 / 450 / 225 volts
Grid-No.1 Voltage ... -14 / -46 / -16.5 volts
Amplification Factor ... 8 / 7.5 / -
Plate Resistance (Approx.) ... 12000 / - / 27000 ohms
Transconductance ... 11000 / - / 9000 µmhos
Plate Current ... 140 / 150 / 87 ma
Grid-No.2 Current ... 12 / - / 4 ma
Grid-No.1 Voltage (Approx.) for plate ma.=1 ... -40 / - / -35 volts

Mechanical:
Operating Position ... Any
Type of Cathode ... Coated Unipotential
Maximum Overall Length ... 4-3/4"
Maximum Seated Length ... 4-3/16"
Maximum Diameter ... 2-1/16"
Bulb ... ST16
Base ... Large-Wafer Octal 8-Pin with Sleeve (JEDEC Group 1, No.B8-86)
Basing Designation for BOTTOM VIEW ... 7S

Pin 1 - Base Sleeve
Pin 2 - Heater
Pin 3 - Plate
Pin 4 - Grid No.2
Pin 5 - Grid No.1
Pin 6 - No Internal Connection
Pin 7 - Heater
Pin 8 - Cathode, Grid No.3

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AF POWER AMPLIFIER - Class A1
Maximum Ratings, Design-Center Values:
PLATE VOLTAGE ... 600 max. volts
GRID-No.2 (SCREEN-GRID) VOLTAGE ... 400 max. volts
GRID-No.1 (CONTROL-GRID) VOLTAGE:
  Negative-bias value ... 300 max. volts
  Positive-bias value ... 0 max. volts
CATHODE CURRENT ... 175 max. ma
GRID-No.2 INPUT ... 6 max. watts
PLATE DISSIPATION ... 35 max. watts
BULB TEMPERATURE (hottest point) ... 250 max. °C

Typical Operation and Characteristics:
Plate Voltage ... 250 / 400 volts
Grid-No.2 Voltage ... 250 / 225 volts
Grid-No.1 Voltage ... -14 / -16.5 volts
Peak AF Grid-No.1 Voltage ... 14 / 16.5 volts
Zero-Signal Plate Current ... 140 / 87 ma
Max.-Signal Plate Current ... 150 / 105 ma
Zero-Signal Grid-No.2 Current ... 12 / 4 ma
Max.-Signal Grid-No.2 Current ... 28 / 18 ma
Plate Resistance (Approx.) ... 12000 / 27000 ohms
Transconductance ... 11000 / 9000 µmhos
Load Resistance ... 1500 / 3000 ohms
Total Harmonic Distortion ... 7 / 13.5 %
Max.-Signal Power Output ... 12.5 / 20 watts
Maximum Circuit Values: Grid-No.1 fixed-bias 0.05 max megohm; cathode-bias 0.25 max megohm

PUSH-PULL AF POWER AMPLIFIER - Class A1 (values for 2 tubes; Fixed Bias / Cathode Bias)
Plate Supply Voltage ... 400 / 600 / 400 volts
Grid-No.2 Supply Voltage ... 275 / 300 / 300 volts
Grid-No.1 Voltage ... -23 / -31 / - volts
Cathode Resistor ... - / - / 140 ohms
Peak AF G1-to-G1 Voltage ... 46 / 62 / 53 volts
Zero-Signal Plate Current ... 180 / 115 / 166 ma
Max.-Signal Plate Current ... 270 / 273 / 190 ma
Zero-Signal Grid-No.2 Current ... 9 / 4 / 7.5 ma
Max.-Signal Grid-No.2 Current ... 44 / 41 / 39 ma
Effective Load Resistance (Plate to plate) ... 3500 / 5000 / 4500 ohms

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(continuation PP Class A1)
Total Harmonic Distortion ... 3 / 2.5 / 4 %
Max.-Signal Power Output ... 55 / 100 / 41 watts
Maximum Circuit Values: Grid-No.1 fixed-bias 0.05 max megohm; cathode-bias 0.25 max megohm

PUSH-PULL AF POWER AMPLIFIER - Class A1 (Triode Connection(d), values for 2 tubes)
Maximum Ratings:
PLATE VOLTAGE ... 495 max. volts
GRID-No.2 (SCREEN-GRID) VOLTAGE ... 440 max. volts
GRID-No.1 VOLTAGE: Negative-bias value ... 330 max. volts; Positive-bias value ... 0 max. volts
CATHODE CURRENT ... 192.5 max. ma
GRID-No.2 INPUT ... 6.6 max. watts
PLATE DISSIPATION ... 44 max. watts
BULB TEMPERATURE ... 250 max. °C
Plate Voltage ... 450 volts
Grid-No.1 Voltage ... -46 volts
Peak AF G1-to-G1 Voltage ... 92 volts
Zero-Signal Plate Current ... 150 ma
Max.-Signal Plate Current ... 220 ma
Effective Load Resistance (Plate to plate) ... 4000 ohms
Total Harmonic Distortion ... 2.5 %
Max.-Signal Power Output ... 28 watts

Footnotes:
(a) The dc component must not exceed 300 volts.
(b) The dc component must not exceed 100 volts.
(c) Without external shield.
(d) Grid No.2 connected to plate.