75 280Z Clock Repair?

[zclocks]

Oh shoot! I'm sorry the drawing should have been crystal clear. 

I think you have it now , but this is what your new installation should look like.

 Did you power up the circuit board with the tran in your configuration?

Ron

[zclocks]

What I ment by "crystal clear" was that the drawing of the 3 transistors  isn't clear. I need to rotate the transistors 180 degrees.

[HusseinHolland]

I did, and needless to say it didn't work. I'll change it out for a new one later.

I was checking the various values of the other measurable items - it appears there are two 670ohm and one 2m ohm resistors.

Zener still drops voltage to 4.4v using a 9v battery. Hopefully I didn't cook anything b sides perhaps the transistor by hooking it up incorrectly. 

My coil resistance values are the reverse of what you posted though?

[zclocks]

Yes, You might have cooked the trans. The coil resistance values can be different and that is why you have 2 -680 ohm resistors . You coil resistance is high and low , but I think it will still work. The normal value of the resistor next to the transistor is 850 ohms. I think they were varying  the resistor value depending on the coil resistance/ inductance. This is why I always stay with the same values of the components of the board I'm repairing. Jeco did some weird things.

[HusseinHolland]

3 hours ago, zclocks said:

Yes, You might have cooked the trans. The coil resistance values can be different and that is why you have 2 -680 ohm resistors . You coil resistance is high and low , but I think it will still work. The normal value of the resistor next to the transistor is 850 ohms. I think they were varying  the resistor value depending on the coil resistance/ inductance. This is why I always stay with the same values of the components of the board I'm repairing. Jeco did some weird things.

Thank you again for your invaluable input Ron.

This is the 3rd resistor, next to the Transistor - looking up the 4 band, it appears to be 2M ohm, unless I'm reading the chart incorrectly

Replaced the transistor (take 2)

it's running now 🙂

 

 

[Captain Obvious]

52 minutes ago, HusseinHolland said:

it's running now

You got to be a little more enthusiastic with the success. You're hiding that little note under all the pics! How about this:

"Woo Hoo!!! MY CLOCK WORKS!!!"

That's what I would do. 

[zclocks]

Captain is right you should be jumping for JOY!!!

 

[Yarb]

Kudos Ron for chiming in to help a fellow member. I personally took notice and appreciated your efforts. Nice job!

[zclocks]

Hey Yarb thanks,

I really like helping when I can. I have been helped many times from this site and when I can pay back I do.

[HusseinHolland]

So, I spoke too soon. The clock worked, but after I reassembled it in the case, it did not. Pulling it back apart, as long as I 'jump start" the wheel, it will run continuously after, but simply connecting it to 12v, nada.

[Captain Obvious]

Did it start by itself on the bench when you had it apart? With a 9V battery?

[HusseinHolland]

1 hour ago, Captain Obvious said:

Did it start by itself on the bench when you had it apart? With a 9V battery?

Honestly, I can't recall now if I 'helped' it. I left it running for a few days off the battery & it kept good time. I'm going to assume I helped it, since it clearly won't jump start itself. Not sure where that leaves me.