Technics Quartz ST-G7 User Manual

adjustment.
[FM ADJUSTMENT
* Setting and Equipment used. * Preparation of FM signal generator (FM-SG)
1. FM signal generator (FM-SG), 1. The standard input of the set is 60 dB (1 mV), 400 Hz, 100%
2. Distortion analyser. modulation (Because of attenuation, using coaxial cables, SG
3. Oscilloscope output must be 6 GB plus, That is, when input 60 dB SG
4. AC and DC electronic voltmeters (EVM). output is to be 66 dB.)
5. Frequency counter (19 kHz and 108 MHz measurable).
6. Set band selector to ‘‘FM" position.
7. Set FM mode selector to ““mono” position. * When the frequency is changed, muting is automatically turned on.
8. Other setting are the same as in AM adjustment. So, be sure to turn it off by the FM muting off/scan level selector switch,
9. Set IF band selector to: ‘‘normal” position. Also, make sure that the FM IF band is at “‘normal’’.
=
FM SIGNAL GENERATOR DISPLAY
PREPARATIONS PARTS ADJUSTED ADJUSTING PROCEDURE
CONNECTION FREQUENCY | FREQUENCY
rbd FM MONO DISTORTION ADJUSTMENT
100.10 MHz Connect DC VEM 1. Adjust T101 core so that
m between PGA and set tile voltage measured in signal
5 pirates 100.10 MHz through choke T101 {Discri. IFT) mode is 0 mV in 300 mV
wilt # coil. (Refer to Fig. 2) range.
Connect
FM-SG
to
100.10
MHz
i
|
Connect
AC
EVM
1.
Adjust
for
maximum
output.
, a :
Bi)
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carried.
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2m
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Sea
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|
abet
care
ch
102
ty
antenna terminal.) (Refer to Fig. 3)
Connect DC VEM 1. Adjust VR102 so that
100.10 MHz VR102 :
7 (0% Mod. 100.10 MHz__| Petween (Pulse count duty voltage measured in
with 400 Hz) and ground, adj.) signal mode isO mV in
(Refer to Fig, 4.) J. 300 mV range.
Short-circuit between MGW and by
jumper wire only during FM-RF adjustment, FM-RF ADJUSTMENT
and be sure to open the circuit during adjustment
other than FM-RF.
1, Scat sc Rey
5 EGET and bE by
Seem, | areata brow ve Bos
8 referririg to’ Eid: 5 (100% Mod, 87.50 MHz 2. Connect DC EVM L6 (OSC Coil) reading on DC EVM.
19 g. ©. with 400 Hz) between fiGAI (+)
(Weak input)
and Ground.
LIOANT Coil} | 1+ Adel woak input ee that
90.10 MHz L1 (ANT Coil
cm | (100% Mod. | 90.10MHz | sgcyepysrserminals, | L3. (ANT Coil) apd auicald acl
g | Connect FM-SG to with 400 Hz) erminals. | 1a (ANT Coil) 2. Make the adjustment so that
antenna terminal T1 (FM 1st IFT) the output wave form is ver-
referring to Fig. 6. tically symmetrical. (Fig. 7).
(Weak input) Tea + 3. Hepes! ihestps (8), (9} and
: 2 10) until the frequency cor-
10 (100% Mod. 106.10 MHz Tent ea CT1 (OSC Trimmer) rectly matches the frequency
with 400 Hz) ‘ display.
PILOT CANCEL ADJUSTMENT
Connect FM-SG to
FM antenna terminal 100.10 MHz : : Make the adjustments so that
‘ : Connect scope L301 (Pilot filter) F
11 referring to Fig. 8. (0% Mod. : the output waveform is
(Apply 60 dB to with 400 Hz) 100.10 MHz between and VR103 (Pilot Cancel) | i pelscring se
antenna terminal.) (L+R) Ground. Fig. 9.
(Pilot 10% Mod.
stereo signal.) L
ess +
STEREO DISTORTION ADJUSTMENT
Connect FM-SG to T
FM antenna terminal 100.10 MHz Connect distortion
refferring to Fig. 10. (90% Mod analyser to “OUTPUT” FE Adjust T1 and T103 core so that
12 (Apply 60 dB to ith ps Hj ) 100.10 MHz terminals of the set EM clea distortion of right and left
antenna terminal.) iL or R mites through low-pass filter. 7 channels are minimized.
(Pilot 10% Mod. (fc = 15 kHz~19 kHz)
stereo signal.)
ST-G7 ST-G7
Note: FM IFT (2nd) [T102], FM 2 nd IF filter [T104, T105] and FM DET filter [L302, L303] have been already adjusted, and require no
FM SIGNAL GENERATOR
: EHeQUENCcY | PREPARATIONS || PARTS ADJUSTED | ADJUSTING PROCEDURE
2.3. CONNECTION FREQUENCY FM Signal gene
tep =
No. SEPARATION ADJUSTMENT KS
Connect EM-SG to 1. Adjust VR303 so that R
: output is minimized when (750)
Bete aay 100.10 MHz Sd eac ta sede stereo modulator is in L e OO
pone (90% Mod. VR303, VR304 (L ch. modulation) mode,
13 {Apply 60 dB to antenna f 100.10 MHz of the set through : °
ermine with 1 kHz) lowe-bese titer (Separation) 2. Adjust VR304 so that L
(Pilot 10% Mod Reta rupae! (fo = 15 kHz ~19 kHz) SutoMs etnies Wien
stereo signal.) stereo modulator is in
:
R
(R
ch
modulation)
mode.
SIGNAL STRENGTH LEVEL ADJUSTMENT
1
1. Change LCD display from
. ee frequency to dB by pressing
onnect -SG to the FM signal button, :
FM antenna terminal. 100.10 MHz VR101 2. Adjust VR101 so that 50 dB FM Signal gener
14 (Apply 50 dB to (30% Mod, 100.10 MHz (Signal strength < indicated
antenna terminal.) with 400 Hz) level) 3. Make sure that the signal bh
strength level is 22 ~ 38 dB
when the input is 30 dB. (750) ff
e OO
e Adjustment points
612 kHz 1503 kHz
19 kHz R—-L L-R FM AM ANT AM ANT
Filter separation separation discri. IFT coil trimmer FM Signal gene
L301]
R304] [VR303]
Computer Control Output | AM ANT
control input terminal), " EXT
AC
inlet
terminal
terminal
——,
{|
Loop
L302 NO ADJUSTMENT
L303 NO
ADJUSTMENT
ADJUSTMENT
T1085 NO TPI03
Ground point
450 kHz
FM ANT
(75Q)
[vRI03 [ti03] [vrioi}] [t2o] [ctr]
19 kHz Pulse count FM IFT Signal strength AMIFT FM 1st FM 1 st
cancel adj. duty adj. (3 rd) level adj. (1 st) Osc. OSC coil
trimmer
AM Signal generator (AM-SG)
r
oO
O' 0
°
OC
AM antenna terminal
7 Output
aad terminal
Capacitor
(200pF)
[Fig. 1] [Abb. 1]
Oscilloscope
me FM ANT
@ S coil
{ L10 |
‘iz | | AM RF coil
L203} 522kHz
FM ANT coil
T coil
T coil
FM Signal gener:

Technics Quartz ST-G7 Specifications

General

Brand	Technics
Model	Quartz ST-G7
Category	Tuner
Language	English