12hp4 crt

[Electronic M]

Originally Posted by WISCOJIM

Probably the same as a 12HP1, except that it has P4 phosphor.

https://frank.pocnet.net/sheets/201/1/12HP1.pdf

.

http://www.mif.pg.gda.pl/homepages/f...3/1/12LP4A.pdf

That tube is ~5" longer than a 12LP4, and uses an 11-pin base instead of the standard 12-pin...Those are obvious enough differences that one would probably notice.

How many pins can the base accommodate, and how many pins are actually populated? (the 12LP4 is a 12-pin but only ~5 are typically populated)
Does the gun look to have electrostatic deflection plates (or leads for them going to the front) in it, or a bend in the lower part of the electron gun for an ion trap? Got pics?

One exceptionally unlikely scenario that would be even harder to mix up is if you scroll down this page: http://www.myvintagetv.com/picture_tubes.htm to the 10HP4 which was a 10" version of the 7JP4 which Raytheon used in some TVs...Maybe the 12HP4 is a 12" 10HP4...If it is that is one rare tube, and one some electrostatic set collectors (myself included) tired of squinting at 7JP4s might want to have.

[dieseljeep]

Originally Posted by Electronic M

http://www.mif.pg.gda.pl/homepages/f...3/1/12LP4A.pdf

That tube is ~5" longer than a 12LP4, and uses an 11-pin base instead of the standard 12-pin...Those are obvious enough differences that one would probably notice.

How many pins can the base accommodate, and how many pins are actually populated? (the 12LP4 is a 12-pin but only ~5 are typically populated)
Does the gun look to have electrostatic deflection plates (or leads for them going to the front) in it, or a bend in the lower part of the electron gun for an ion trap? Got pics?

One exceptionally unlikely scenario that would be even harder to mix up is if you scroll down this page: http://www.myvintagetv.com/picture_tubes.htm to the 10HP4 which was a 10" version of the 7JP4 which Raytheon used in some TVs...Maybe the 12HP4 is a 12" 10HP4...If it is that is one rare tube, and one some electrostatic set collectors (myself included) tired of squinting at 7JP4s might want to have.

The data sheet that Jim cited shows the CRT is an E-stat deflection and focusing.

[Kevin Kuehn]

If the base and envelope really look similar to a 12LP4, I'd plug it into my tester and slowing bring up the filament voltage and see how it tests. I can't imagine the envelope of an electrostatic tube being mistaken for a magnetically deflected. Can you post a picture here?

[grimer]

Here is a link,the 4th pic is a projector tube from the same place..
https://www.toadstation.com/12hp4

[Polaraligned]

Try testing as a 12LP4 and see what happens.

[grimer]

Originally Posted by Polaraligned

Try testing as a 12LP4 and see what happens.

Well,that was my thought to,I would just start at a lower filament voltage,as
mentioned in one of the other posts....

[Kevin Kuehn]

I'm going to guess Progressive Electronics was some place selling radio and TV parts to DIY types and that they sold used or rebuilt CRTs and came up with their own tube type designation.