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Old 05-01-2026, 01:26 PM
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Quote:
Originally Posted by TinCanAlley View Post
I think I found the horizontal sync issue, maybe. The 755 horizontal driver transistor tests good as far as not being shorted, etc. However, the hFE is zero. According to the specs of the ECG157, it's replacement, it should have a minimum hFE of 30.

Ordered an OEM replacement.
You must not be measuring hFE correctly. A transistor cannot test good with a hFE of zero.

If the driver transistor were dead, you likely would not have horizontal scan at all. The driver transistor is very unlikely to be the cause of intermittent sync.

Again, if some function is intermittent, you should applied mechanical tapping, pressing and jiggling to find an intermittent connection.
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