Service manual
Pin | Symbol | Function |
19 | VSW | AFC switch |
20, 21 | VVCO | VCO circuit |
22 | VAFC | AFC output |
23 | VS | Supply voltage |
24 | VO, FM | Intercarrier output |
25 | VO, AM | AF |
26 | RCOMP | Offset compensation |
27, 28 | Vi,SIF2 | SIF2 input (symmetrical) |
4-3-4 Block diagram
| Offset |
| Loop |
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| l' switch |
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| comp. |
| filter | VCO |
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| 26 | 18 | 20 | 21 | 14 |
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| VCO | Control |
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| FPLL |
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| + |
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| phase shift |
| 19 |
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| AFC | |
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| AFC |
| switch |
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| 22 |
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| AFC | |
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| 6 | VIF amp |
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VIF | 7 |
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| Video |
CAGC |
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| Video det. |
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| 8 |
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| Standard |
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| AGC |
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| 13 | |
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| switch | ||
| 15 |
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| Standard |
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| (VIF) |
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| CBL |
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Tuner | 11 |
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| 23 | V |
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| 10 | Tuner |
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| Supply |
| 17 |
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| AGC |
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Take over |
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| FM det. |
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| Cref |
point |
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27 |
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| 24 |
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SIF 2 | 28 |
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| Intercarrier |
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| SIF amp |
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| (FM/NICAM) | |
SIF input |
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switch | 3 |
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| 1 |
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SIF 1 | 2 |
| AGC |
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| 25 | AF |
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| (SIF) |
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| (AM) |
| 5 |
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| AM det. |
| 4,9,16 | |
CAGC |
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