7189

ampage tube data		ampage tube data

7189
POWER PENTODE

Pin Element

1 none

2 Control Grid

3 Cathode & Supressor Grid

4 Heater (Filament)

5 Heater (Filament)

6 none

7 Plate (Anode)

8 none

9 Screen Grid

Miniature type used
in the output stage
of high-fidelity audio-
frequency amplifiers.
Requires miniature
9-contact socket.
See also 6BQ5.

Heater Voltage (AC/DC)	6.3	volts
Heater Current	0.76	ampere
Heater Warm-up Time (Average)	11	seconds

Peak Heater-Cathode Voltage
Heater negative with respect to cathode	100 max	volts
Heater positive with respect to cathode	100 max	volts

Direct Interelectrode Capacitance
Grid No.1 to Plate	0.5	pf
Grid No.1 to Cathode, Heater, Grid No.2, and Grid No.3	10.8
Plate to Cathode, Heater, Grid Ho.2, and Grid No.3	6.5
Grid No.1 to Heater	0.25

CLASS A₁ AMPLIFIER

CHARACTERISTICS
Plate Voltage	250	volts
Grid-No.2 Voltage	250
Grid-No.1 (Control-Grid) Voltage	-7.3
Mu-Factor, Grid No.2 to Grid No.1	19.5
Plate Resistance (Approx.)	40000	ohms
Transconductance	11300	umhos
Plate Current	48	ma
Grid-No.2 Current	5.5

PUSH-PULL CLASS AB₁ AMPLIFIER

Maximum Ratings (Design-Center Values)
Plate Voltage	400	volts
Grid-No.2 (Screen-Grid) Voltage	300	volts
Cathode Current	65	ma
Plate Dissipation	12	watts
Zero Signal Grid-No.2 Input	2
Maximum Signal Grid-No.2 Input	4

Typical Operation (Values are for two tubes)
Plate Supply Voltage	250	300	volts
Grid-No.2 Supply Voltage	250	300	volts
Cathode-Bias resistor	130	130	ohms
Peak AF Grid-No.1-to-Grid No.1 Voltage	22.6	28.3	volts
Zero-Signal Plate Current	62	72	ma
Maximum-Signal Plate Current	75	92
Zero-Signal Grid-No.2 Current	7	8
Maximum-Signal Grid-No.2 Current	15	22
Effective Load Resistance (Plate-to-plate)	8000	8000	ohms
Total Harmonic Distortion	3	4	%
Maximum-Signal Power Output	11	17	watts

Maximum Circuit Values
Grid No. 1 Circuit Resistance
For fixed-bias operation	0.3	megohm
For cathode-bias operation	1	megohm