Re: Tek 213 Battery connector


tss_steve_990
 

Larry wrote in response to my questions:

 

I'm going to guess that your male connector on the board goes to the
trace rotation coil and crt shield (2 blacks & a red in the middle) -- it
comes out the neck of the shield beside the crt.

Steve:

Now starts the very bad news.  The three wires from inside the CRT shield are not present on this scope.  I removed the CRT from the scope and from its shield and found the coil but the wires had been pulled off the trace rotation coil.  I find 2 broken magnet wire ends. The first end closer to the neck and the other end closer to the face of the CRT.

The bigger problem is the rattling sound emanating from inside the CRT.  There is a round, metal disc-shaped element inside the CRT (maybe a getter?) which has become completely detached from wherever it was originally attached inside and has apparently been rattling around inside the CRT for quite a while.  I had noticed earlier that the internal phosphor coating was peppered with lots of tiny scratches in it, not like burn marks, but like the inside coating was mechanically scratched.  Now that I have discovered the little disc inside, it makes sense that it has scratched the inside surface of the phosphor coating on the face plate.

The filament (Pins 1` and 2) is intact and measures about 1.5 Ohms cold.

I believe I did find a 2 pin header that is probably for the CRT filament on the PS PCB.  The two male pins were kind of splayed wide and smashed, so I thought they were maybe test points.  They have a couple of low value resistors in series with them – maybe 1 Ohm.

I don’t know if It is safe to even try to operate the unit with the loose element inside the CRT.  Depending on how the scope was carried would determine where the piece would land on every power-on.    It seems to me that without a new CRT, this unit is not going to be salvageable.

I found the plastic pins, and your description of how the battery pack is held in place was helpful.

 

Steve

 

 



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