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Author Topic: Question about T4148 diode  (Read 612 times)

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Offline bshi02Topic starter

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Question about T4148 diode
« on: May 21, 2024, 04:33:19 am »
I have 29 inch CRT TV which only display black screen.
After I switched on it and I heard inrush of current,I measured voltage of pin #9 of STR-S6707(6.2-6.4 DCV). and I found that DCV(placing red probe to cathode terminal of diode) of ZD808(it is written B75 on its surface) was 6.8-7V and D805 and positive pin of C811 was 6.4-6.6V , D807 and positive pin of C812 was 13-13.2V, But D806(it is written T4148 on its surface) was 0.5-0.7V like below schematic which I drawed STR-S6707 and its adjacent components in circuit . It is doubt whether D806 is faulty diode or not.
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Offline m k

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Re: Question about T4148 diode
« Reply #1 on: May 31, 2024, 12:11:09 pm »
STR-S6707 datasheet covers STR-S6709.
Maybe it's demo circuit can give some thoughts.
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Offline kevin.gibbs

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Re: Question about T4148 diode
« Reply #2 on: August 22, 2024, 02:10:18 am »
In general, 0,5-0,7V should drop on the diodes. Therefore, it is likely in good working order. You can unsolder one of the leads for complete confidence and then check the diode with a multimeter.
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