<< 805 Vacuum Tube


Classification- Dome-type bulb of glass, filametary of carbennation Th-w a white ceramic base with four-prong bayonet golden pins, carbon plate triode.

Application -Audio power amplifier A-F, R-F of class B or R-F of class C and H-F oscillater.

Dimensions -Dimensions, outline diagrams of the tube and bases, and the arrangement of electrode connections to the base terminals are shown in Figures 1 and 2.
 
Fig 1
 
Fig 2
 

Nominal operating conditions and parameters
Filament voltage ¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­ 10V
Nominal filament current ¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­ 3.2A
Plate voltage ¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­ 900V
Grid voltage ¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­ 20V
Plate current ¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­ 110mA

Suggest operating conditions and parameters
A-F of Class B Power amplifier(two tube)
Limiting value
V
Plate voltage
1250
1500
1500
V
La (max. sig. per tube)
210
mA
Pa (in)(max. sig. per tube)
315
W
Pa (per tube)
125
W
Grid voltage
-16
V
Ug~ (pk)
235
280
V
La (O)
148
84
mA
La (max. sig)
500
600
mA
Pd
6
7
W
Load resistance (a-a)
6.7
8.2
kohms
Pout (max. sig)
300
370
W

R-F of class B power amplifier of push-pull

Limiting value
Plate voltage
800
1000
1000
1250
V
Plate current
125
170
175
225
mA
Load resistance
4.5
4.6
4.6
6.6
kohms
Grid voltage
80
70
40
40
V
Signal voltage(pk)
177
240
V
Output power
40
75
75
115
W

R-F of class B power amplifier

Limiting value
Plate voltage
1250
1500
1500
V
Plate current
135
115
150
mA
Grid current
15
15
mA
Grid voltage
10
V
Signal voltage(pk)
70
70
V
Output power
55
57.5
W
Pd.
11
7.5
W
Plate dissiplation
85
W

R-F of class C power amplifier of single tube(max modulate coefficient shall be 1)

Limiting value
Plate voltage
1000
1250
1250
V
Plate current
160
160
175
mA
Grid current
60
60
70
mA
Grid voltage
-155
-160
-500
V
Signal voltage(pk)
295
300
V
Output power
110
140
85
W
Pd.
16
16
W
Plate dissiplation
125
W

R-F of class C power amplifier and oscillater(each tube of key contral conditions for note modulate)

Limiting value
Plate voltage
1000
1250
1500
1500
V
Plate current
200
200
200
210
mA
Grid voltage
-95
-100
-105
-500
V
Signal voltage(pk)
225
230
235
V
Output power
130
170
215
W
Pd.
8.5
8.5
8.5
W
Plate dissiplation
125
W

Characteristics-Average characteristics
Figure 3. shown typical curves of plate currents of grid voltage for several values of plate voltages. It is alternating-current filament supply.
Fig 3

Limiting Operation Conditions for Safe Nor simultaneous ratings
Maximum plate voltage ¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­ 1250 volts
Maximum plate dissipation ¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­ 75 watts