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gary
Joined: 05 Apr 2005
Posts: 584
Location: MANCHESTER, uk
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 Posted: Thu Sep 28, 2006 3:58 pm Post subject: |
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| the scan coils are the big lump round the neck of the crt. usually though if there is a fault there the output waveform from ic501 would be affected, were the + & - 15v supplies to ic501 correct? sometimes 1 of them will be low and cause this problem |
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Guest
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| Posted: Sat Oct 07, 2006 5:42 pm Post subject: |
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| Gary I am only getting .03v across pins 1 & 7 of the ic501 |
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gary
Joined: 05 Apr 2005
Posts: 584
Location: MANCHESTER, uk
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| Posted: Mon Oct 09, 2006 3:56 pm Post subject: |
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| supply is on pins 2 & 4 if correct change the ic, pins 1 & 7 are drive, check with an oscilloscope not a meter |
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Toon
Joined: 20 Sep 2006
Posts: 7
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| Posted: Tue Oct 17, 2006 12:44 am Post subject: |
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Gary I am only getting 3v across 2 & 4 pins, Any ideas?
Thanks |
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gary
Joined: 05 Apr 2005
Posts: 584
Location: MANCHESTER, uk
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| Posted: Tue Oct 17, 2006 3:53 pm Post subject: |
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| check r514 & r515, should be .47r sometimes go high in value |
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Toon
Joined: 20 Sep 2006
Posts: 7
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| Posted: Sun Oct 29, 2006 11:20 am Post subject: |
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The reading I’m getting 0.49r on both resistors is this ok or is it slightly high. Taking into consideration my tester could be out as its never been calibrated since the day I got it about 10 years ago  .
Thanks again for your help. |
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gary
Joined: 05 Apr 2005
Posts: 584
Location: MANCHESTER, uk
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| Posted: Mon Oct 30, 2006 9:18 am Post subject: |
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| that value is ok, try replacing ic501 |
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