▼ Menu

7025WA

Sensibly equivalent to:
7025A
    
Extras ▼

 

The 7025WA is a low hum audio amplifier double triode and an improved version of the 7025 The WA suffix denotes a special quality type.
This valve was designed for high gain small signal amplification. The 6.3 Volt heater rating is with the voltage applied between 4 + 5 and pin 9. When used with the connections made to pins 4 and 5 the rating is 12.6 at 0.15 Amp. The electrical characteristics and pin connections almost match the ECC83.
Side view - one anode seen face-on.
The two anodes seen side by side. The box anodes are considerably larger than the ECC83.
An angled shot showing the ends of the grids. The implementation uses double micas to give protection in environments subject to vibration.
The thin glass tube envelope is 22 mm in diameter, and excluding the B9A base pins is 48 mm tall.
Reference: Datasheet.

 

Pin Connections
B9A
1
2
3
4
5
6
7
8
9
a(2)
g1(2)
k(2)
h
h
a(1)
g1(1)
k(1)
hct

 

Absolute Maximum Operating Conditions
Pentode
Vh
Ah
Va
Vg
mAa
ra
gm
μ
6.3
0.3
250
-2
1/2
62,500
1.6
100
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated May 03, 2016.
Return to Main Index