| ampage tube data |
ampage tube data |
|---|
| 7408 BEAM POWER TUBE | ||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|  |
Glass octal type used
as output amplifier tube in high-quality sound systems. Tubes require octal socket and may be mounted in any position. | ||||||||||||||||||
| Heater Voltage (AC/DC) | 6.3 | volts |
| Heater Current | 0.45 | ampere |
| Heater Warm-up Time (Average) | 11 | seconds |
| Heater-Cathode Voltage | Average | Peak | |
|---|---|---|---|
| Heater negative with respect to cathode | 100 max | 200 max | volts |
| Heater positive with respect to cathode | 100 max | 200 max |
| Direct Interelectrode Capacitance (Approx.) | ||
|---|---|---|
| Grid No.1 to Plate | 0.7 | pf |
| Grid No.1 to Cathode, Heater, Grid No.2, and Grid No.3 | 9 | |
| Plate to Cathode, Heater, Grid Ho.2, and Grid No.3 | 7.5 | |
| CLASS A1 AMPLIFIER |
| Maximum Ratings (Design-Maximum Values) | ||
|---|---|---|
| Plate Voltage | 350 max | volts |
| Grid-No.2 (Screen-Grid) Voltage | 315 max | |
| Plate Dissipation | 14 max | watts |
| Grid-No.2 Input | 2.2 max | |
| Typical Operation and Characteristics | ||||
|---|---|---|---|---|
| Plate Voltage | 60 | 250 | volts | |
| Grid-No.2 Voltage | 250 | 250 | ||
| Grid-No.1 (Control-Grid) Voltage | 0 | -12.5 | ||
| Peak AF Grid-No.1 Voltage | - | 12.5 | ||
| Zero-Signal Plate Current | 100 | 45 | ma | |
| Maximum-Signal Plate Current | - | 47 | ||
| Zero-Signal Grid-No.2 Current | 22 | 4.5 | ||
| Maximum-Signal Grid-No.2 Current | - | 7 | ||
| Plate Resistance (Approx.) | - | 50000 | ohms | |
| Transconductance | - | 4100 | umhos | |
| Load Resistance | - | 5000 | ohms | |
| Total Harmonic Distortion | - | 7 | % | |
| Maximum-Signal Power Output | - | 4.5 | watts | |
| Maximum Circuit Values | ||
|---|---|---|
| Grid No. 1 Circuit Resistance | ||
| For fixed-bias operation | 0.1 max | megohm |
| For cathode-bias operation | 0.5 max | |