B&K 470 CRT tester problems.

[Eric H]

Hi all, picked up this tester fairly cheap but with some issues.

First try it didn't work at all, you could do all the set up except the G-2 was dead, found and replaced an open Red G-2 pot with an exact replacement part.

Now you can do the setup but when you switch it to the "Emissions" setting the meter swings past the Good scale and smacks the stop, you can turn the G-2 control down and bring the needle down but then of course the G-2 setup is off.

I am using my 5AXP4 test tube for this, primarily because it's like new, using an older 10BP4 I can't set the G-2 at all even though I can with my other 466 tester.

I suspect the G-2 is more than it should be, the meter is supposed to deflect one small division when you adjust the G-2 but at that setting the meter pegs when reading emission.

I've checked all the resistors and Diodes, cleaned the switches (which were clean to start with) and replaced one 4.7mf Cap.
There are two 47@450 caps still not replaced but they seem to be OK but what else is left?

There are no adjustments inside except a Heater Calibration pot, I think that just adjusts the meter to match the voltage.