TUBEOFILE
Search
Compare
FAQ
Tube+
Sign In
Sign In
☰
Loading...
849 — Power Triode, Jumbo3 | Tubeofile
← Browse
849
Power Triode — DHT — Jumbo3
···
+ Compare
RCA
↗ TDSL
↗ Radiomuseum
Known Equivalents & Substitutes
CV2669
Similar Tubes (Not Drop-In Compatible)
211
Smaller transmitting triode (75W Pa_max vs 300W); same general application class but much lower power capability
845
Smaller transmitting triode (100W Pa_max vs 300W); same UX4 pinout family but different base and much lower power rating
Electrical Specifications
Absolute Maximum
Anode Voltage (max)
Plate Voltage (max)
3,000
V
Anode Dissipation (max)
Plate Dissipation (max)
300
W
Cathode Current (max)
Plate Current (max)
350
mA
Typical Operating
Anode Voltage (typical)
Plate Voltage (typical, Class A)
3,000
V
Grid 1 Bias Voltage
Grid Voltage (Class A)
-132
V
Anode Current
Plate Current (Class A)
100
mA
Anode Resistance
Plate Resistance
3,250
Ω
Transconductance
Transconductance
Output
Output Power
Output Power (Class A)
100
W
Load Impedance
Load Resistance (Class A)
18,000
Ω
Heater
Heater Voltage
Filament Voltage
11
V
Heater Current
Filament Current
5
A
Notes
DHT tube: the thoriated tungsten filament serves as the cathode; there is no heater-cathode isolation.
Maximum plate current is 350 mA.
The plate (anode) connection is made via a top cap; the base carries only filament and grid connections.
Class A amplifier at Va=3000V: Vg=-132V, Ia=100mA, mu=19, gm=5.8 mA/V, ra=3250 Ohm, rl=18000 Ohm, Po=100W.
Designed primarily for broadcast transmitter service; also used in high-power SE audio amplifiers.
Pa_max is 300W (CCS). The tube requires forced-air cooling in most installations at full ratings.
Filament may be operated on AC or DC. Grid bias voltage is referenced to filament midpoint.
Pin Layout — Jumbo3
1
2
3
1
Filament
2
Grid
3
Filament
TC
Top Cap —
Plate (Top Cap)
Socket-Compatible Tubes
⚠ Not electrically compatible
851
References
https://tdsl.duncanamps.com/show.php?des=849
https://www.radiomuseum.org/tubes/tube_849.html
5.8
mA/V
Amplification Factor (μ)
Amplification Factor
19
—