Data set 01
1951 Mullard Valve and Service Manual
Published operating points and test conditions from this source.
SECTION 1
Pentode
Application
Service
Line time-base output
Power - TV Horizontal Output (sweep) ·Pentode
EL38
High-power output pentode primarily designed for television line time-base output, providing approximately 25 W plate dissipation and substantial voltage/current swing.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- Octal
- Socket code
- IO
- Base pins
- 8
- Nominal heater
- 6.3 V / 1.4 A
Description
Output pentode primarily intended for television line time-base (horizontal deflection) output service.
Socket description
International Octal
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- Octal
- Socket code
- IO
- Base pins
- 8
- Nominal heater voltage
- 6.3 V
- Nominal heater current
- 1.4 A
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
Octal - 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
Pentode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 20000 Ω
- Transconductance
- 0.014 S
- Amplification factor
- 16.5
- Max plate voltage
- 400 V
- Max screen voltage
- 400 V
- Max plate dissipation
- 25 W
- Max screen dissipation
- 6 W
- Max cathode current
- 200 mA
Published source values promoted where applicable; additional values retained as parameters.
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 02
1963 Mullard
Published operating points and test conditions from this source.
SECTION 1
Pentode
Other
Anode current
150 mA
LineOutput; design value
Typical anode current
225 mA
LineOutput; average new valve
Peak anode voltage
8 kV
LineOutput
Data set 03
1967 Mullard Receiving Tubes for Maintenance
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristic
Plate voltage
275 V
Screen-grid voltage
275 V
Plate current
91 mA
Screen-grid current
11 mA
Control-grid voltage
-9 V
Transconductance
14 mA/V
Plate resistance
20 kOhm
Amplification factor grid1-grid2
16.5
Other
Supply voltage
300 V
LineTimeBase
Plate current
64 mA
LineTimeBase
Screen-grid current
18 mA
LineTimeBase
Peak plate voltage
8000 V
LineTimeBase
Maximum plate voltage
800 V
Maximum plate dissipation
25 W
Maximum screen-grid voltage
400 V
Maximum screen-grid dissipation
8 W
Maximum cathode current
200 mA
Capacitance
Input capacitance
18 pF
Output capacitance
8 pF
Anode-control-grid capacitance
1.2 pF
Maximum
Data set 04
1999 Philips E-Z
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristic
Kapezitdten Ca
645 pF
CQ8‘|
1.2 pF
Va - 250 €
0 v
Vg2 = 250
400 V
Vet = -7
-22 v
Ia = 100
42 mA
s = 14,3
7 ma/V
Vg1 (Ig1 = + [1]
0.3 pa
Vg1 (Ig1 = + [2]
1.3 V
Rgy (Wg
< 9 W
Rgt1 (Wa
> 9 W
Vit max.,
100 V
Other
max
800 V
Va P maxe
4 kV
Vg max
25 W
Vg2 max
400 V
Wgz max
8 w
Ix max
200 mA