CR-70 and a 10MP4

[jeyurkon]

Originally Posted by jr_tech

I doubt if the RMA/RETMA/EIA would have allowed two different tubes to exist with the same type number. The RMA registration (to Sylvania) 10/16/49 shows NOTHING connected to pin 10. I suspect an error in the tube checker data. Do you get a reading if you tie the extra wire to the anode button?
I have never seen a 10MP4 ... what set was it used in?

jr

I didn't try the anode, but I did something similar earlier. Using my B&K CRT tester I wired in a 10KV supply to the anode. I was able to check the G1 cutoff this way, but not the emission. I figured if the G1 was good then the CRT stood a good chance of being good.

The set has always worked best with over the air signals. My laserdisc player gave the next best results. Recently it seemed like it wasn't performing as well as it did a few months ago. After trying to test it with the CR-70 I tried hooking the laserdisc player up to an Agilant modulator to see if that would be better. The laserdisc player was completely dead. That may have been the cause. Seems like the bridge rectifier has given up the ghost. Some more repair work ahead.

Thanks for the confirmations everyone.

John