Specialized - Cathode Ray ·CathodeRay
Eight-inch P4 cathode-ray display tube for high-voltage direct visual service, using magnetic deflection and manufacturer-specified focusing, grid-control, and accelerating-voltage characteristics.
The Sylvania 8YP4 is a 8-inch wide-angle P4 receiver-check CRT with self-focusing electrostatic gun and magnetic deflection.
Small-shell Duodecal 5-contact CRT base
General specifications
Properties common to every published source and operating point.
Electrical assignments shared by every tube using this base designation.
| Terminal | Section | Connection | Evidence |
|---|---|---|---|
| PIN1G1 | A | G1 — Control Grid EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 7FG |
| PIN2IS | A | IS — Internal Screen EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 7FG |
| PIN3H | — | H — Heater EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 7FG |
| PIN4H | — | H — Heater EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 7FG |
| PIN5P | A | P — Plate (Anode) EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 7FG |
| PIN6G2 | A | G2 — Screen Grid EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 7FG |
| PIN7K | A | K — Cathode EIA transcription; manufacturer confirmation pending | Unverified EIA Base Connections, printed page 129, 7FG |
1 physical section, each with unique specifications.
Section 1
Cathode-ray section. CRT anode/ultor, grid, focus/deflection, heater-cathode, capacitance, and operating values are stored as section parameters.
Source-dependent data
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 01
Published operating points and test conditions from this source.
Maximum Plate Voltage
22000 V
Typical Anode Voltage
16000 V
Phosphor
P4
Focusing Method
Self Focusing (Electrostatic)
Deflecting Method
Magnetic
Data set 02
Published operating points and test conditions from this source.
Heater Voltage
6.3 V
Heater Current
600 mA
Focusing Method
Self-Focusing Electrostatic text
Deflection Method
Magnetic text
Deflection Angle
110 deg
Approximate
Phosphor
P4 text
Fluorescence
White text
Persistence
Short to Medium text
Cathode-to-All Capacitance
5 pF
Approximate
Grid1-to-All Capacitance
6 pF
Approximate
Vertical Deflection Angle
87 deg
Horizontal Deflection Angle
105 deg
Maximum Anode Voltage
22000 V
Maximum Grid2 Voltage
550 V
Maximum Grid1 Negative Bias
155 V
RepresentativePublishedLimit
Maximum Grid1 Positive Peak
2 V
Maximum Heater-Cathode Voltage During Warmup
450 V
Duration<=15s
Maximum Heater-Cathode Voltage After Warmup
200 V
Anode Voltage
16000 V
Grid2 Voltage
300 V
Grid1 Cutoff Voltage Minimum
-72 V
Grid1 Cutoff Voltage Maximum
-35 V
Maximum Grid1 Circuit Resistance
1.5 Mohm
Data set 03
Published operating points and test conditions from this source.
Cathode to All Other Electrodes Capacitance
4 pF
Grid #1 to All Other Electrodes Capacitance
6 pF
Focusing Method
Electrostatic self-focus
Deflecting Method
Magnetic
Deflection Angle
110 deg
Anode Voltage
- to 22000 V
Design maximum
Grid #2 and Grid #4 Voltage
- to 550 V
Grid #1 Negative Peak Voltage
- to 220 V
Grid #1 Negative Bias Voltage
- to 155 V
Grid #1 Positive Bias Voltage
- to 0 V
Grid #1 Positive Peak Voltage
- to 2 V
Peak Heater-Cathode Voltage - Heater Negative During Warm-Up
- to 450 V
Warm-up period <=15 s
Peak Heater-Cathode Voltage - Heater Negative After Warm-Up
- to 200 V
Peak Heater-Cathode Voltage - Heater Positive
- to 200 V
Anode Voltage
16000 V
CathodeDrive
Grid #2 and Grid #4 Voltage
400 V
CathodeDrive
Cathode Voltage for Visual Extinction
42 to 78 V
CathodeDrive
Grid #1 Circuit Resistance
- to 1.5 MΩ
Maximum circuit value