Representative Test Data - Racal Instruments RA-117 User Manual

12. Representative Test Data

Signal Input to: Frequency
(a) Junction of 1,000 c/s
C218 and C221B 1,000 c/s
(b) Grid V16 100 kc/s c.w
Grid V14 100 kc/s c.w
Socket SKT303 100 kc/s c.w
(c) Grid of 2.2 Mc/s c.w 25 V
second mixer
(TP3) 2.5 Mc/s c.w 25 V
2.9 Mc/s c.w 25 V
(d) Aerial input 3.5 Mc/s c.w 250mV
(WIDEBAND
75-ohms)
(e) Aerial input 3.5 Mc/s c.w 250mV
(WIDEBAND
75-ohms)
(f) Grid V10 37 5 Mc/s c.w 100 V
Grid V8
TP1
(g) With the 1 Mc/s crystal in place, the output at socket SKT2 should be approximately
Input Output
0 8V 50mW in 3 ohms
1 0V 10mW in 600 ohms R.F. & I.F. GAIN
(output to line)
360mV 100 A R.F.
level
850 V 100 A R.F.
level
GAIN MAX.
800 V 100 A R.F.
level
100 A R.F.
level
100 A R.F.
level
100 A R.F.
level
0.5 at TP2
0.5 at TP3
1V at TP3
70 V
8mV
[30]
Remarks
AUDIO GAIN MAX.
A.F. LEVEL MAX.
MIN. B.F.O. off.
LIMITER off.
B.F.O. off
SYSTEM switch
MAN. R.F./I.F.
1Mc/s and 1 7Mc/s
crystals removed. V.F.O.
switch set to EXT.
Mc/s scale set to 20.
BANDWIDTH 3kc/s.
1 Mc/s and 1 7Mc/s
crystals
re-inserted.
V.F.O. switch set
to INT. Image response
(i.e. receiver frequency
plus 200 kc/s) should be
at least 60db down.
WIDEBAND 75-ohms
INPUT R.F.
ATTENUATOR MIN. V5
and V7 removed. Valve
voltmeter input shunted to
12pF.
WIDEBAND INPUT
R.F. ATTENUATOR
MIN. V5 and V7 refitted.
V9 and 1 Mc/s crystal
removed. Valve voltmeter
input shunted to 12pF.
MEGACYCLES scale 3.
V9 and V5 and 1Mc/s
crystal removed
Valve volt- meter input
shunted to 12pF.