Valve & Amplifier Design @ ValveData on SlideShare, EL34 (6CA7) Data Sheets from Mullard Valves.

1. OUTPUT PENTODE
Output pentode rated for 25W anode dissipation,
ntended for use in a.c. mains operated equipment.
PRELIMINARY DATA
HEATER
Vh 6.3 v
Ih 1.5 A
CAPACITANCES
Cout 7.2 pF
Cln 15.5 pF
C&-gl <1.1 pF
Cgl-h <1.0 pF
Ck-h 11 pF
CHARACTERISTICS
Va 250 v
v go 250 v
Vgs 0 v
la 100 mA
Igo 14.9 mA
Vgl -13.5 V
gm 11 mA/V
ra 15 kil
(.I.gl-gO 11
OPERATING CONDITIONS AS SINGLE VALVE CLASS "A"
AMPLIFIER
Pentode connection
Va 250 V
Vg2 250 V
Vga 0 V
Vg1 -13.5 V
Rk 120 (1
la 100 mA
Ig2 14.9 mA
R. 2.0 k(1
V1n (r.m.B.) (Pout=50mW) 0.5 V
*Pout 11 W
V1n (r.m.B.) 8.7 V
*Dtot 10 %
*Pout and Dtot are measured at fixed bias and therefore represent the
power output available during the reproduction of speech and music.
When a sustained sine wave is applied to the control grid the bias
across the cathode resistor will readjust itself as a result of the
increased anode and screen-grid currents. This will result in
approximately 10% reduction in power output.
ISSUE 2 EL34 256-1

2. OUTPUT PENTODE
Output pentode roted for 2SW onode dissipotion,
intended for use in a.c. mains operated equiPment.
OPERATING CONDITIONS FOR TWO VALVES IN PUSH-PULL
Distributed load conditions with screen-grid tapping at 43% of
primary turns
V"J-VRk 430 430 v
Rg2 (per valve) 1 1 kO
Vg2+VRk 425 425 V
18(0) 2 x 62.5 2 x 62.5 mA
18 (max. sig.) 2x65 2x70 mA
Ig2(0) 2x5.0 2x5.0 mA
Ig2 (max. sig.) 2x5.1 2x7.5 mA
Rk (per valve) 470 470 O
V1n(gl-gl) r.m... 32 52 V
R8-8 6.6 6.6 kO
Pout 20 37 W
Dtot 0.8 1.3 %
OPERATING CONDITIONS FOR TWO VALVES IN PUSH.PULL
Fixed bias
Vb 425 375 y
"Rg2 1000 470 O
Vg2 0 0 y
18(0) 2x30 2x35 mA
la (max. sig.) 2x120 2x120 mA
Ig2 (0) 2x4.4 2x4.7 mA
Ig2 (max. sig.) 2x25 2x25 mA
Vg1 -38 -32 y
R8-a 3.4 2.8 kO
V1n (gi-g 11 r.m.8. 54 45 y
Pout 55 44 W
Dtot 5.0 5.0 %
*Screen-grid resistor common to both valves,
These operating conditions apply with a stabilised line voltage and
allow for a 25V drop in the primary winding of the output trans-
former at maximum signal. If there is an additional drop of 25V
in the h.t. line voltage at maximum signal Pout=45W and 36W.
The optimum anode-to-anode load under these conditions are
4.0kD. and 3.8kD. respectively.
ISSUE 2 EL34 256-2

3. OUTPUT PENTODE
Output pentode rated forc25W anode dissipation,
intended for use in a.c. mains operated equipment
OPERATING CONDITIONS FOR TWO VALVES IN PUSH-PULL
With separate screen-grid supply and fixed bias
Vb(a) 500 800 V
Vb(g2' 400 400 V
*Rg2 750 750 !1
Vg:J 0 0 V
Ja(O; 2x30 2x25 mA
la (max. sig.) 2x125 2x91 mA
Ig2(o, 2x4.0 2x3.0 mA
Ig2 (max:sig.) 2x25 2x19 mA
Vg1 -36 -39 V
Ra_a 4.0 11 k!1
VIR (g,-g,) r.m.B. 51 47 V
, PC))1~ 70 100 W
I Dto1 5.0 5.0 %
,
*Screen-grid resistor common to both valves.
These operating conditions apply with stabilised line voltages and
allow for a 2SV drop in the primary winding of the output trans-
former at maximum signal. If there is an additional drop of 25V
in the line voltages at maximum signal Pout=58W and 90W. The
optimum anode-to-anode load under these conditions are 5.0k!1
and 11 kO respectively.
OPERATING CONDITIONS FOR TWO VALVES IN PUSH.PULL
Cathode bias
Vb 375 V
*Rg. 470 O
tRk 130 O
Vg. O V
la(ol 2x75 mA
la(max.sig.) 2x95 mA
Ig.(ol 2x11.5 mA
In (max.c5jgr) ! 2 x 22.5 mA
Ra_a 3.4 kO
V1n(gl-gl) r.m.8. 42 V
Pout 35 W
Dtot 5.0 %
*Screen-grid resistor common tO both valves.
tCommon cathode bias resistor.
These operating conditions allow for a 20V drop in the primary
winding of the output transformer and a 5V drop in the h.t. line
voltage at maximum signal.
ISSUE 2 EL34 1056.3

4. OUTPUT PENTODE
Output pentode rated far 25W anode dissipation,
intended for use in a.c. mains operated equipment.
OPERATING CONDITIONS AS SINGLE VALVE CLASS "A"
AMPLIFIER
Triode connection (g2 connected to a, ga to k)
Va+VRk 375 v
V 0 v
R~a 370 O
la 70 mA
Vgl -26 V
Ra 3.0 kO
V1n (r.m.s.) (Poul=50mW) 1.7 V
Poul 6.0 W
V1n (r.m.s.) 18.9 V
Dlo1 8.0 %
OPERATING CONDITIONS FOR TWO VALVES IN PUSH-PULL
Triode connection (g2 connected to a, g3 to k)
V,,+VRk 400 430 V
V83 0 0 V
*Rk 220 t250 .0
I,,(o) 2x65 2x64 mA
I" (max. sig.) 2x71 2x67 mA
V81 -29 -32 V
R"_,, 5.0 10 k.O
V1n (81-81)r.m.s. 44 48 V
Poul 16 14 W
D1o1 3.0 <1.0 %
*Common cathode bias resistor.
tUn-bypassed.
LIMITING VALUES
Va(b) max. 2.0 kV
Va max. 800 V
Pa max. 25 W
Pa max. (max. signal speech and music) 27.5 W
V lI(b) max. 800 V
VII max. 425 V
pgo max. 8.0 W
Ik max. 150 mA
Vn max. (In=+0.3!J.A) -1.3 V
Rn-k max. (cathode bias) 700 k.Q
Rn-k max. (fixed bias) 500 k.Q
Vh-k max. 100 V
Rh-k max. 20 k.Q
ISSUE 2 EL34 1056.4

5. OUTPUT PENTODE
Output pentode roted for 2SW anode dissipation,
intended for use in a.c. mains operated equipment.
~
92 91
a HC
q2
h h
q3 k
Oclal Bas,
ISSUE2 EL3~ 1056-5
~

6. OUTPUT PENTODE
Output pentode rated for 25W anode dissiPation,
intended for use in a.c. mains operated equiPment.
ANODE AND SCREEN-GRID CURRENT PLOTTED AGAINST CONTROL
GRID VOLTAGE
ISSUS;2 EL34 1056-6

7. OUTPUT PENTODE
Output pentode roted for 25W onode dissipation,
intended for use in a.c. mains operated equiPment.
~ ~
0- I
> >
."'
O "i'
"""
-' "
..."'
::'
>
O
II
I~
,0.:~..
0
a..
HE ~ ~
ANODE CURRENT PLOTTED AGAINST ANODE VOLTAGE WITH
CONTROL-GRID VOLTAGE AS PARAMETER Vg.=250V
ISSUE 2
@ EL34 357.7

8. OUTPUT PENTODE-
Output pentode rated for 25W anode dissipation,
intended for use in a.c. mains operated equipment.
ANODE CURRENT PLOTTED AGAINST ANODE VOLTAGE WITH
CONTROL GRID VOLTAGE AS PARAMETER Vg2=360V
cW ~
ISSUE 2 EL34 357-8

9. OUTPUT PENTODE
Output pentode rated for 25W anode dissipation,
intended for use in a.c. mains operated equipment.

10. OUTPUT PENTODE
Output pentode rated for 25W anode dissipation,
intended for use in a.c. mains operated equipment.
~'(.;.w.J
(000000 00000 O Oj)~O~OO--m
;!i
, .+~..
I l' .I
0
2
-:1 ~ ,
-ti
:J',
I
I
~
>--
+
~ ~
~-
-o
.-!
~:,
1. »c:~$
:;. ~~.~'!'
c
:. ..
]~ .
&
::r;. , .,
~
~Ei
05::=.
!(VUI)1
0
~ ~
(..IU,)(I6-I!).!~ ~ o
o
0
. ~
N
PERFORMANCE OF TWO EL34 IN PUSH-PULL WITH DISTRIBUTED LOAD
CONDITIONS. SCREEN-GRID TAPPING AT 43% OF PRIMARY TURNS
ISSUE 2 EL34 105610
@

11. OUTPUT PENTODE
Output pentode roted for 25W onode dissipotion,
intended for use in a.c. mains operated equipment.
.
~
c 0
> Q E
°
OM
::;.
~:
~
+
(vw)I ~
l""'A)U!A ~
0
. ~
~Ofo) ...0 ~ 2
PERFORMANCE OF TWO EL34 IN PUSH-PULL WITH FIXED BIAS AND
Vb=375V
ISSUE 2
e EL.34 1056-1 f

12. OUTPUT PENTODE
Output pentode rated for 25W anode dissipation,
intended for use in a.c. mains operated equipment.
;;
12
.,"'; " , "
(Vw)1 9 9 8 o
-~- "' -
, ( .."A ) U!A O
-0
0
. ~
(010)
.O.a ~ ~
PERFORMANCE OF TWO EL34 IN PUSH-PULL WITH FIXED BIAS AND
Vb=425V
ISSUE 2 EL34 1056-12

13. OUTPUT PENTODE
Output pentode rated for 25W anode dissipation,
intended for use in a.c. mains operated equipment.
PERFORMANCE OF TWO EL34 IN PUSH-PULL WITH SEPARATE ANODE
AND SCREEN-GRID VOLTAGE SUPPLIES AND FIXED BIAS V"(b)=SOOV,
Vg2(b)=400V
ISSUE 2 EL34 256-13
@

14. OUTPUT PENTODE
Output pentoderated for 25W anode dissipation,
intended for use in a.c. mains operated equiPment.
PERFORMANCE OF TWO EL34 IN PUSH-PULL WITH SEPARATE ANODE
AND SCREEN-GRID VOLTAGE SUPPLIES AND FIXED BIAS Va(bl=800V.
V"(b)=400V
ISSUE 2 EL3. 256.11
1@

15. OUTPUT PENTODE
Output pentode rated for 25W anode dissipation,
intended for use in a.c. mains operated equipment.
PERFORMANCE OF TWO EL34 IN PUSH-PULL WITH CATHODE BIAS
AND Vb=37SV
ISSUE 2 EL34 1056-15
~

16. OUTPUT PENTODE
EL34
ISSUE 2 EL34 1056-16

17. OUTPUT PENTODE
Output pentode rated for 25W anode dissipation,
intended for use in a.c. mains operated equiPment.
PERFORMANCE OF TWO EL34 IN PI,JSH-PULL TRIODE CONNECTED
ISSUE 2 EL34 1056-17