Normally, R5 (top left corner) charges C3 for the delay. C3 is discharged quickly through D3. If C3 is open or D3 shorted, you could lose the delay. The attached diagram is included in case your board has different circuit board designations.
If Q4 is shorted, the same loss of delay could occur. A shorted Q4 may have destroyed the new Q5.
If Q4 is shorted, the same loss of delay could occur. A shorted Q4 may have destroyed the new Q5.
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The voltage across Q5 should be very near 0v.
The original transistors in Q4/5 locations had relatively high Hfe. The ones that you're using are lower. The lower gain with 270k of resistance will not allow Q5 to pull down far enough.
If you give me a list of the transistors you have, I may be able to find a working combination. Or, you can order the originals.
The original transistors in Q4/5 locations had relatively high Hfe. The ones that you're using are lower. The lower gain with 270k of resistance will not allow Q5 to pull down far enough.
If you give me a list of the transistors you have, I may be able to find a working combination. Or, you can order the originals.
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