Who was it that had NOS or rebuilt CRT's for sale? I have a fellow collector who is in need of a 21MP4 or equivalency.

He had a long list of available tubes. Thanks folks!!

Bobhas these for sale; don't know if any of them will sub for the tube you are looking for.

Oops, for some reason that link does not take you to the page; go to the FOR SALE menu on the left, the CRTs

http://antiquetvguy.com/Frameset%20Pages/HomepageFrameSet1.html

It's a metal cone crt. No sub for it.

It's a metal cone crt. No sub for it.

They used to have a kit for installing a 21ZP4, in place of a 21AP4 in RCA sets. It worked really great.
The 21MP4 is an electrostatic focusing tube. It can be subbed by a 21AP4, but you have to use a magnetic focusing unit.
I depends on what make of set it is. I've converted a few other makes. :thmbsp:

I've got a NOS Continental Electronics 21MP4 in storage that I could make available. I can probably get to it over the coming weekend and test it. Shipping always concerns me when dealing with CRTs though. I'll send you a PM.

Julian:

I received a message that your PM box is full and not accepting any new messages. I used the e-mail option here but not sure if you received it. Send me a PM if still interested.

Regards,