Anyone familiar with a SEncore cr70 tester?

[ohohyodafarted]

I am looking at the test resutls from a Sencore cr70 for a crt that I might possibly buy.

I am not familiar with this tester, but it appears that the G1 and G2 voltages are set to obtain a set point on the meter, individually for each gun.

If the G1 and G2 settings vary greatly from gun to gun, does this indicate that there is a large difference in emmission from gun to gun?

I can send photos of the test results via PM if there is someone here who can interpret the results for me, that would be appreciated.

Thanks,
Bob

[rcaman]

i have had one of those for years . send me the results and i will see what i can do for you.

[ohohyodafarted]

Thanks RCAman here are the results... tube is a 21axp22

red gun k=4 g1=2 g2=3
green k=5.5 g1= 6.5 g2=7
Blue k=13 g1=12 g2=11

For each gun, the pointer on the meter is set at a red mark between 12 and 13 on the scale in the good area. So I am assuming that the positions of k, g1 and g2 are set to acheive a pointer reading on that mark and that interpreting the settings on the 3 knobs (k, g1,g2) determines the strength of the gun.

I have actual photos if you want to see them. But I would need to send them to your regular e-mail address as attachments. I could try to reduce the size of the jpegs but at present they are about 1.3mB each.

Thanks much,

Bob Galanter

[ohohyodafarted]

Still need help here. Anyone...PLEASE jump in if you know how to interpret these readings.

Thanks,
Bob

[Nakdoc]

I do not recognize the readings. The CR 70 has fixed g2. The cutoff is set with a variable control that I assume produces a specified cathode current. Under full emissions test g1 is raised and the tube is good if the cathode current tracks the increase in bias. The CR 70 is largely a go / nogo tester. It does have an aging test, which measures the drop in emissions with reduced heater voltage. A good tube will drop very little.
Relevant measurements would be the position for RGB of the g1 in the cutoff set mode, and the cathode current in emissions test.