Testing: 3KP4 vs 7JP4 on Sencore CR70

[Phil Nelson]

I just got a Sencore CR70 CRT tester and have been happily testing everything in sight, except my single 3KP4 for which no settings are given.

This tester has a universal adapter with little clips that you connect to CRT pins for heaters, grids, etc. Works fine to test a 7JP4.

I have seen oldgoat's Youtube video about testing a 3KP4. Seems like all he did was build an adapter cable for the CRT.

http://www.youtube.com/watch?v=wZH-nRMSnPw

Is there some technical reason why my unit can't test a 3KP4 or did Sencore omit 3KP4 from their chart simply because it was so little used?

http://scottbecker.net/tube/sheets/049/3/3KP4.pdf

http://scottbecker.net/tube/sheets/137/7/7JP4.pdf

I'd like to check the 3KP4 in my Pilot TV-37, but it's the only one in the house, so I'm leery of rash experiments.

Phil Nelson

[bandersen]

I love those oldgoat videos

The 3KP4 seems to have lower recommended operating voltages than the 7JP4 so I'm thinking the test results won't be valid. Anode voltages are a lot less too.

Does the Sencore put out high voltage to the anode or just test the emission?

[mbates14]

too bad the guy lost his workshop. i feel sorry for him, too bad i didnt live closer, i would help him move and setup.

[Phil Nelson]

Originally Posted by bandersen

Does the Sencore put out high voltage to the anode or just test the emission?

No HV, just an emission test. It also test shorts, cutoff, does life test, rejuvenate/restore, etc., but what I'm most curious about is emission.

Phil