▼ Menu

PenA4

Sensibly equivalent to:
4066A 420T 42MP/Pen 7A2 7A3 A70C A70D AC2/Pen APP4B ARP10 ARP25 CV1181 CV3638 KT41 N41 NR59 OP42 PT4 Pen4VB TL44
    
Extras ▼

 

The PenA4 is an audio pentode power output valve.
For the heater power the emission is not high and the audio output achieved is small. It is specified for single ended use, as would be found in radio receivers.
The top mica area. The copper supports for the control grid are topped with a heat radiating fin.
The classic envelope is 49 mm in diameter and, excluding the B7 base pins, is 120 mm tall.
References: Data-sheet, Data, private correspondence & 1043 Type PenA4 was first introduced in 1937. See also 1937 adverts.

 

Pin Connections
B7
1
2
3
4
5
6
7
nc
g1
g2
h
h
k
a

 

Absolute Maximum Operating Conditions
Pentode
Vh
Ah
Va
Vs
Vg
mAa
mAs
ra
gm
Pout
D
4.0
1.95
250
250
-5.8
36
5.0
50,000
9.5
3.8W
10%
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated January 19, 2023.
Return to Main Index