Alignment Instructions - AMSTRAD MS-45/F Service Manual

ALIGNMENT INSTRUCTIONS
Equipment Required:
1. AM signal generator 6. Nonmetallic alignment tool
2. FM signal generator 7. AF oscillator
3. IF sweep generator with marker capabilities 8. Frequency counter
4. Oscilloscope 9. Distortion meter
5. VTVM
Important:
. Check line voltage.
. Set function switch to band being aligned.
. Set the loudness switch to off.
. Remove the antenna from the terminal.
. Set tone control to high.
. Connect low side of signal source and output indicator to chassis ground (unless otherwise specified).
Ground connection should be kept close to high side connection.
7. Signal input should be kept as low as possible to avoid AVC and AFC action.
(Set output indicator to high sensitivity.)
8. Standard modulation is 1000Hz at 30% amplitude for AM (1000Hz at 22.5kHz deviation for FM).
OmA Gh —
AM IF
Speaker
output
LorR
4 ohm load
Figure 1
AM Section
Circuit Alignment | Equipment Connection Dial Setting Adjustments
465 kHz Tuning gang T3 (AM IFT)
IF
a niGae. fe
(1000 Hz Mod.)) fully closed
Adjust for maximum output.
(See Fig. 1) Repeat until no further improvement can be made.
AM BAND/TRACKING
I
'a hs 2feet —— 1
t (60cm)
AM SG
Speaker G
A output s poninidiene
| jack
GO
Loop Ant.
D> ea
AM Ant.
Figure 2