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AC5/PenDD

Sensibly equivalent to:
CV1196 NR87
See also:
CV1196 short entry
    
Extras ▼

 

The AC5/PenDD is a double diode output pentode with a high mutual conductance. For a local station superhet receiver the diodes provide the demodulation and the AGC voltage whilst the pentode takes the demodulated audio and directly drives the loud speaker without the need for an initial voltage amplifier stage.
The output impedance is 5,200 Ω and the cathode resistor for cathode bias is 180 Ω. The power output is given as 4.85 Watts.
Although described as a pentode it is believed that the output stage is actually a beam tetrode.
It is difficult to see the actual construction or where the diode anodes are located.
The classic envelope is 54 mm in diameter, and excluding the B9A base pins is 125 mm tall.
References: Data-sheet, 1040 & 1043. Type AC5/PenDD was first introduced in 1938. See also 1938 adverts.

 

Pin Connections
B7
1
2
3
4
5
6
7
tc
a(d2)
a
a(d1)
h
h
k
g2
g1

 

Absolute Maximum Operating Conditions
Pentode
Vh
Ah
Va
Vs
Vg
mAa
mAs
gm
4.0
2.0
250
250
-8.5
40.0
7.5
9.4
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated April 09, 2020.
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