Data set 01
1953 RFT Rundfunk Technik
Published operating points and test conditions from this source.
SECTION 2
Diode
Other
Peak diode voltage
200 V
Maximum diode current
0.8 mA
SECTION 3
Pentode
Application
Application
RF_IF_AF_Amplifier text
Voltage Radio Detector Converter ·Diode-Diode-Pentode
UBF11
Series-heater diode-pentode combining receiver detection with high-resistance small-signal amplification. The pentode supplies receiver gain while diode sections provide detector or control-voltage rectification.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 3
- Base
- -
- Socket code
- P8A
- Base pins
- 8
- Nominal heater
- 20 V / 100 mA
Description
The UBF11 combines a controllable pentode with two diodes. It is specified for RF, IF and audio amplification, includes fixed- and sliding-screen regulation data, and provides diode sections for detection and control-voltage generation.
Socket description
European 8-pin side-contact base
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- P8A
- Base pins
- 8
- Nominal heater voltage
- 20 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
3 physical sections, each with unique specifications.
Section 1
Diode
X-ray radiationInterelectrode capacitances
- Max plate voltage
- 200 V
- Max cathode current
- 0.8 mA
Diode 1.
Section 2
Diode
X-ray radiationInterelectrode capacitances
- Max plate voltage
- 200 V
- Max cathode current
- 0.8 mA
Diode 2.
Section 3
Pentode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 1500000 Ω
- Transconductance
- 0.0018 S
- Max plate voltage
- 250 V
- Max screen voltage
- 250 V
- Max plate dissipation
- 1.5 W
- Max screen dissipation
- 0.3 W
- Max cathode current
- 10 mA
Pentode section; maximum and characteristic values promoted.
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
1957 Philips Receiving and Amplifying Tubes
Published operating points and test conditions from this source.
SECTION 3
Pentode
Characteristics
Cutoff characteristic
Variable-mu
Application
Application
RF / IF amplifier
Data set 03
1959 Telefunken
Published operating points and test conditions from this source.
SECTION 3
Pentode
Other
Plate voltage
200 V
Pentode;ScreenVoltage=80V
Screen voltage
80 V
Pentode
Control-grid bias
-2 V
Pentode
Plate current
6 mA
Pentode
Screen current
2 mA
Pentode
Characteristics
Reduced transconductance
18 uS
RegulationRatio=100:1
Capacitance
Input capacitance
7.5 pF
Pentode
Grid-plate capacitance
<0.003 pF
Pentode