KT88
11 Tubes in archive
BrandGenalex
ClassBeam Pentode
BaseOctal
Filament6.3V @ 1.6mA
Construction
Primary TypeBeam Pentode
EnvelopeTubular
Base MaterialMetal shell wafer octal
Filament / Heater
Heater NotesIndirectly heated
Absolute Maximum Ratings
Plate Voltage600 V
Plate Dissipation35 W
Grid 2 Voltage600 V
Cathode Current175 mA
H-C Voltage150 V
Audio Performance
Typical THD1%
Power Output100 W
Key Features
- Beam Pentode
- Metal shell wafer octal base
- Indirectly heated
- Up to 100W output for a pair
- 150W intermittent Class B operation
Typical Operation
| Mode | Plate V | Gm (µmhos) | Rp (Ω) | µ | Plate mA |
|---|---|---|---|---|---|
| Pentode Connection | 250V | 11000 | 12000 | 8 | 140mA |
| Triode Connection | 250V | 12000 | 670 | 8 | 160mA |
| Push-Pull Ultra-Linear (Cathode Bias) | 500V | - | - | - | 174mA |
| Push-Pull Ultra-Linear (Fixed Bias) | 560V | - | - | - | 100mA |
Application Notes
The KT88 is primarily designed for the output stage of an a.f. amplifier for which two valves will provide up to 100W output. It is also suitable for use as a series valve in a stabilised power supply.
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