Forgot to connect DAG to Neck PCB

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Finished a K4900 rebuild, and fired the game up, heard the HV crackle and no display but did get a smell of burning components. I was wondering what was going on!?!?

I shut it down and began to scratch my head and that's when I noticed that I had forgotten to insure the DAG was connected to the neck PCB.

Suffice it to say, it no workie no more.........

What "usually" goes up in smoke when someone as stupid as I does something as lame as this?

Thanks in advance.
Jeff
 
The ground wire on my K7something neckboard isn't connected to the tube... it pulled out of a spade connector, and since it works, I've been lazy. However, it's still connected to the HV board, so maybe it's reaching ground anyway...
 
Finished a K4900 rebuild, and fired the game up, heard the HV crackle and no display but did get a smell of burning components. I was wondering what was going on!?!?

I shut it down and began to scratch my head and that's when I noticed that I had forgotten to insure the DAG was connected to the neck PCB.

Suffice it to say, it no workie no more.........

What "usually" goes up in smoke when someone as stupid as I does something as lame as this?

Thanks in advance.
Jeff

I don't think the 4900 causes the same issues as a K7000 when not hooking up the dag wire. I'm pretty sure I've seen them work without it connected, although I always try to connect it (even via jumper) when testing.

Do you have any idea what burned up - if anything? When you hook up the dag - what happens? What is the B+? Fuse blown?
 
After I finished flogging myself for not checking everything before powering it up, I did connect the DAG and fired it up and received no picture, so I just walked away to calm down.

I will go back tomorrow and check all fuses, get a HV reading and see what damage was done.

Thanks
Jeff
 
I pulled the chassis, desoldered the fuse on the chassis and it tested good.

I pulled the HOT (Q352) and got some strange readings with my DMM set to diode test.
With the negative probe connected to base, I probed the collector and emitter and got .472v and .029v
With the positive probe connected to base, I probed the collector and emitter and got O/L and .029v

I think that these readings are due to the internal configuration of the HOT.

Can I get verification that these readings are normal.

Thanks
Jeff
 
Gee now your joining the monitor chassis killing crew?

Finished a K4900 rebuild, and fired the game up, heard the HV crackle and no display but did get a smell of burning components. I was wondering what was going on!?!?

I shut it down and began to scratch my head and that's when I noticed that I had forgotten to insure the DAG was connected to the neck PCB.

Suffice it to say, it no workie no more.........

What "usually" goes up in smoke when someone as stupid as I does something as lame as this?

Thanks in advance.
Jeff
 
I've dealt with stress that would be hard to explain but the 3 Children situation is unprecedented in it's effectiveness in scrambling the minds of men.........
 
I don't know what I did but it now works!
I resoldered the fuse into place, hooked everything up and got picture.

Did something "reset" on the chassis??

Well - anyway, it works so I'm happy and will try not to do this again...
Jeff
 
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