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Service Technical Information
| MODEL NO. | SUFFIX |
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| TV− C1421 / C1422 | KER / KE |
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| TV− C2121 | SHR |
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| SUBJECT |
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| A beat noise problem |
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| REF No :G − A 2− 0 0 2− E 0 | |
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| DATE :3 0 . M A Y . 2 0 0 2 | |
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<CONTENTS>
A beat noise problem may arise by influence of the power supply circuit. Especially, this problem will happen in low electric field or VHF LOW channel.
<COUNTERMEASURE>
To avoid being influenced, modify the power circuit as following countermeasure.
1.Replace the FB830 and FB831 in the secondary stage of the power supply to the jumper wires. (see fig.2)
2.Remove the JW606 and JW608 which connect the GND traces.(see fig.3)
3.Replace the JW801 at the primary stage of the power circuit to the ferrite beading.(see fig.4)
9
8
JW801
FB
Rectifier circuit | 7 |
(TV− C2121 only)
6
5
4
3
2
PT801
10
11
FB830 
JW
12 | 115V |
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15
16
FB831 
JW
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13V
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18
fig.1
| Ref. | Parts Code | Description |
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| Remarks | ||||
JW801 | 87− 003− 320− 080 | −F BEAD,FBR07HA121NB |
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| Code No. |
| Access Code | Modified Ser. No. |
| Parts Schedule | |
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