I have attached a portion of the circuit containing Q1. The problem is that as soon as the circuit is powered (12VDC) up, the TR relay energizes. When this first occurred it was cycling in and out, but now TR picks up and stays pulled in.
The CD4060 pin 3 (output ) is still low ).001V and there is 10.8 V across TR(at D1). I first suspected D2 and cut one lead- no change. I replaced Q1, R5, and C4, still no change. only 1.4- 1.9 v across Q1 EC
after many voltage measurements, calculations and head scratching, today I cut R5, and C4 still no change.
I have double, and triple checked the polarity of Q1(PN2222ATA) and double checked the board for shorts, I also attached a screen shot of the board layout.
I am at a loss. hopefully someone can give me a clue.
If you want more details, see page 3 of my previous thread,http://forum.allaboutcircuits.com/showthread.php?t=68755
The CD4060 pin 3 (output ) is still low ).001V and there is 10.8 V across TR(at D1). I first suspected D2 and cut one lead- no change. I replaced Q1, R5, and C4, still no change. only 1.4- 1.9 v across Q1 EC
after many voltage measurements, calculations and head scratching, today I cut R5, and C4 still no change.
I have double, and triple checked the polarity of Q1(PN2222ATA) and double checked the board for shorts, I also attached a screen shot of the board layout.
I am at a loss. hopefully someone can give me a clue.
If you want more details, see page 3 of my previous thread,http://forum.allaboutcircuits.com/showthread.php?t=68755
Attachments
-
79.2 KB Views: 63
-
57.6 KB Views: 45