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18. Valve Data
INTRODUCTION
1. Details of valves used in the receiver are given in Tables 1 and 2 overleaf. The location
of valves is shown in fig. 8 and valve base connections are given in the circuit dia-
gram. Voltages were obtained from a B9A or B7G stand-off valve base using a 20,000
ohms/volt meter on the optimum range in each case. Valve pin numbers are indicated
in brackets in Table 2.
2. The receiver was set as follows:-
(1) SYSTEM switch to MAN.
(2) R.F./I.F. GAIN to MAX.
(3) No signal i.e. first and second v.f.o. off tune.
(4) B.F.O. off except for checking V19.
(5) SYSTEM switch to CAL in order to check V13 and V15 only.
TABLE 1.
Pin
6AK5W
6ES8
6AS6
6BA6
6688
12AT7
6BE6W
6AL5
6AQ5
No.
M8100
ECC189
EF93
E180F
ECC81
EB91
1
Grid1
Anode2
Grid1
Grid1
Cathode
Anode2
Grid1
Cathode1
Grid1
2
Cathode
Grid2
Cathode
Grid3
Grid1
Grid2
Cathode
Anode2
Cathode
& Grid3
& Grid5
& Grid3
3
Heater
Cathode2
Heater
Heater
Cathode
Cathode2
Heater
Heater
Heater
4
Heater
Heater
Heater
Heater
Heater
Heater
Heater
Heater
Heater
5
Anode
Heater
Anode
Anode
Heater
Heater
Anode
Cathode2
Anode
6
Grid2
Anode1
Grid2
Grid2
I.C.
Anode1
Grid2
Screen
Grid2
& Grid 4
7
Cathode
Grid1
Grid3
Cathode
Anode
Grid1
Grid3
Anode1
Grid1
8
Cathode1
Grid 3
Cathode1
& Screen
9
Screen
Grid2
Heater C.T.
Base
B7G
B9A
B7G
B7G
B9A
B9A
B7G
B7G
B7G
TABLE 2
Cct.
Type
Ref.
Anode
Screen
Cathode
American
Equivalent
Function
V1
140(5)
75(6)
1.16(2)
6AK5W
M8100
Crystal osc./
amplifier
V2
165(5)
120(6)
3.0(2)
6AK5W
M8100
Harmonic
generator
V3
172(1)
-
1.1(8)
6ES8
ECC189
R.F.amplifier
90(6)
V4
175(5)
120(6)
2.0(2)
6AS6
Harmonic mixer
V5
175(5)
95(6)
-
6BA6
EF93
First v.f.o.
V6
196(5)
85(6)
0.95(2)
6BA6
EF93
37.5 Mc/s
amplifier
V7
173(7)
120(9)
0.85(1)
6688
E180F
First mixer
[67]
Summary of Contents for RA-117
Page 1: ...Racal RA 117 Radio Receiver...
Page 24: ...Detailed Circuit Description 24 at maximum is the correct calibration maintained...
Page 32: ...32...
Page 70: ...Illustrations 70...
Page 71: ...Illustrations 71...
Page 72: ...Illustrations 72...
Page 73: ...Illustrations 73...
Page 74: ...Illustrations 74...
Page 75: ...Illustrations 75...
Page 76: ...Illustrations 76...
Page 77: ...Illustrations 77...
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