Zenith Advanced System 3 picture tube testing

[zeno]

To test the jug use the universal adapter & the "common"
settings ( dont remember what they were). Green & retrace
could be H-GK short, tap neck wile running & see if it
flashes. Can also hang a meter on GK & pull socket while running.
Normal K voltage abt 100V - 130V, if low with socket on but normal
off its the tube.
Set can shut down with excessive beam current BUT it must warm
up 1st. Can be caused by:
Excessive G2 voltage
loss of 200 V supply for the R,G, & B transistors.
A dead shorted H-K may also.
Sometimes these sets would come in with the power supply out.
Fixed them, looked OK then a few weeks later back again.
The CRT's arced & blew the supply. Most I saw bad were from
low emission or drifting grey scale followed by shorts & arcs.
It also affected cheap models more so I would guess they put
a better grade in the high end sets ( they deny that).

73 Zeno