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Voltage - Triode (single) ·Triode

AC701

Low-noise, low-microphony audio preamplifier triode for condenser microphones and other very-high-input-resistance applications.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
4 V / 100 mA

Description

Low-noise, low-microphony AF triode preamplifier for condenser microphones and other very-high-input-resistance applications.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
4 V
Nominal heater current
100 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

Terminal pinout

Electrical assignments shared by every tube using this base designation.

No verified pinout is recorded for this base designation.

Section ratings

1 physical section, each with unique specifications.

Section 1

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.0028 S
Amplification factor
23
Max plate voltage
120 V
Max plate dissipation
0.5 W
Max cathode current
5 mA

Published Telefunken ratings and characteristics promoted from the supplied source. Telefunken AC701 low-noise condenser microphone preamplifier triode. Continuous anode voltage maximum 120 V, zero-current voltage limit 250 V, anode dissipation maximum 0.5 W, cathode current maximum 5 mA. Amplification factor 23; transconductance 2.8 mA/V at 60 V plate voltage, -1.6 V grid bias.

Source-dependent data

Operating conditions by source

Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.

Data set 01

1959 Telefunken

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • HeaterOrFilamentVoltage

    4 V

  • HeaterOrFilamentCurrent

    100 mA

  • Application

    Condenser microphone preamplifier

  • LowNoiseDesign

    1 boolean

  • LowMicrophonyDesign

    1 boolean