Rca 21-t639

[bgadow]

That bent metal arrangement is there to hold the tube in place, often used on rectifier and horizontal output tubes, especially on sets with a vertical chassis (the chassis is up and down, usually wrapped around the neck of the crt, instead of laying flat on the bottom of the cabinet) this was common around the time your RCA was made. You need to push down on both sides of that spring while pulling the tube out. I know, because those HV cages are tight it can be unnerving to have both hands down in there. You can discharge the HV by shorting the picture tube HV lead to chassis ground. One method is to get a large, straight slot screwdriver and connect its shaft with a jumper wire to the chassis, then stick the tip behind the connector of the crt so that it shorts. You will hear a snap if there is voltage stored there. Leave it there for a few seconds and then do it again. Then it will be safe enough to work in the cage no matter what you touch, provided the set is unplugged!

You wouldn't need to ship the whole set for repairs, you could just send the chassis to someone who could use a test CRT to power it up. Still a pain to ship but doable.