An electron cannon emits electrons in a very narrow straight beam, which is (was) than magnetically deflected by heavy electromagnets mounted on the neck of the tube. If you create a deflection circuitry with a deflection equal in all directions, you get a circle. Hence the round screen. In order to make it rectangular the power and accuracy required to accurately push the electron beam in the corners requires much more powerful and complicated circuitry, and therefore a more expensive TV.
From: 'orange_glow_fan' via neonixie-l [mailto:neonixie-l@googlegroups.com] Sent: Thursday, January 07, 2021 5:41 PM To: neonixie-l <neonixie-l@googlegroups.com> Subject: Re: [neonixie-l] Re: Fascinating film about 1960s colour CRT manufacturing When Color TV's first came on the market in the early 50's all of them had round CRT's. The first ones were 15" CRT's. Around 1954 RCA introduced a 21" round CRT and they were the standard until around 1963 when the first rectangular CRTS entered the market. I suspect this film was made during the short time when both versions were available. The first practical, consumer color tv was introduced by RCA in 1953 and they sold about 4,000 of them at a cost of $1,000, about $8,000 dollars in 2021 dollars... On Thursday, January 7, 2021 at 4:19:16 PM UTC-5 Bill van Dijk wrote: I believe the round tubes were for the cheaper TVs. From: neoni...@googlegroups.com <mailto:neoni...@googlegroups.com> [mailto:neoni...@googlegroups.com] On Behalf Of Yohan Park Sent: Thursday, January 07, 2021 3:50 PM To: neonixie-l <neoni...@googlegroups.com <mailto:neoni...@googlegroups.com> > Subject: [neonixie-l] Re: Fascinating film about 1960s colour CRT manufacturing Enjoyed watching that, thanks for sharing. Any idea what the large round tubes were used for back then? On Thursday, January 7, 2021 at 1:40:27 PM UTC+1 mikeselectricstuff wrote: https://www.youtube.com/watch?v=7IrSLPVkxCo -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+...@googlegroups.com <mailto:neonixie-l+...@googlegroups.com> . To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/a1e53271-e44a-437a-ab0f-d6f58c0a7b64n%40googlegroups.com <https://groups.google.com/d/msgid/neonixie-l/a1e53271-e44a-437a-ab0f-d6f58c0a7b64n%40googlegroups.com?utm_medium=email&utm_source=footer> . -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com <mailto:neonixie-l+unsubscr...@googlegroups.com> . To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/9595732c-e19c-4243-b1a1-e5c8c4da75d9n%40googlegroups.com <https://groups.google.com/d/msgid/neonixie-l/9595732c-e19c-4243-b1a1-e5c8c4da75d9n%40googlegroups.com?utm_medium=email&utm_source=footer> . -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/019801d6e553%24a5ce5f20%24f16b1d60%24%40gmail.com.
