- 7jp4
The 7JP4 is an early black and white
cathode ray tube used in late 1940stelevisions . It has a 7" diameter round screen which was often partially masked. Unlike laterelectromagnet ically deflected TV tubes, the 7JP4 iselectrostatic ally deflected like an oscilloscope tube.Because it is electrostatically deflected and was obsolete by the mid 1950s, most CRT testers will not test the 7JP4 and thus it is best tested in a working TV set. One notable exception is the
Jackson 707 Cathode Ray Tube Analyzer which is capable of testing the 7JP4 along with the3KP4 and other electrostatically deflected CRTs.----
External links
* [http://tubedata.tigahost.com/tubedata/sheets/137/7/7JP4.pdf Datasheet]
* [http://www.antiqueradio.org/televisions.htm Phil's Old Radios TV gallery]
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