It is absolutely true. A consciencous station would have one or two typical home color TVs, connected to good outdoor antennas and not cable, in the control room to see and know what their viewers were seeing at home. Because of the design compromises of consumer TVs, especially in the color decoding circuitry and the lack of DC restoration, tweaks were made to be sure the home viewer was pleased. I worked in the TV repair craft between 1967 and 77, and there was a lot progress made and very bad compromises as well. Remember, a nice 23 inch console color set would cost $2500-4000 in today's money. Now you can buy a 45 inch high definition hang on the wall flat screen color set for $300 or less.
Bruce Gentry, KA2IVY
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On 11/16/20 3:48 PM, stevenhorii wrote: In the days of color CRTs for television, I knew a guy who worked in a broadcast studio. Though Trinitron displays (Tektronix made a display monitor that used a Trinitron CRT) were used in the control room of the studio, he said that they also had a conventional triangular dot shadow mask monitor as that was what most home TVs used and they wanted to be sure that the broadcast image looked as good on the triangle shadow mask monitor as it did on the Trinitron ones. Whether or not this is true, I don't know.
Steve H.
On Mon, Nov 16, 2020 at 3:38 PM Dennis Tillman W7pF <dennis@ridesoft.com> wrote:
Hi Barry, As with so many things there is an excellent explanation on Wikipedia of shadow mask and Trinitron tubes and how they work. It is at https://en.wikipedia.org/wiki/Cathode-ray_tube. Scroll down to the section I am referring to. No magic is involved, just a shadow mask. Dennis Tillman W7pF
-----Original Message----- From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of n4buq Sent: Monday, November 16, 2020 9:43 AM To: TekScopes@groups.io Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"
Hi Tom,
My question is probably quite simple but, like I said, I'm not finding a good answer.
As I understand it (and from personal observation when I had a Trinitron TV and I'm primarily wondering about this type of CRT but the question probably applies to others), the screen has groupings of RBG phospher dots and the RGB guns "activate" those dots as needed; however, what I'm not understanding is how a given gun "activates" a given dot. Is a particular phosphor dot sensitive to a property of one of the color guns such that a blue dot ignores a red gun, etc.? If so, then I can somewhat understand it but I'm wondering if I'm way off in that assumption.
The various sites just seem to indicate there are three guns, each of which magically cause a given color to appear but it's not explained how a single color gun causes a corresponding dot to glow without affecting the ones around it.
(Hope that made sense...)
Thanks, Barry - N4BUQ
----- Original Message -----
From: "Tom Lee" <tomlee@ee.stanford.edu> To: TekScopes@groups.io Sent: Monday, November 16, 2020 11:27:46 AM Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"
Hi Barry,
Pete's book mainly covers electrostatically deflected crts. Except for some very early models, TVs used magnetically deflected crts (to allow large screens without absurd set depths). The guns are similar, but the deflection methods are very different because of the different optimization objectives.
--Tom
-- Prof. Thomas H. Lee Allen Ctr., Rm. 205 350 Jane Stanford Way Stanford University Stanford, CA 94305-4070 http://www-smirc.stanford.edu
On 11/16/2020 07:18, n4buq wrote:
Does anyone know whether this book covers CRTs that were used for color TVs (and other color displays)? I ask because I'm not finding good information on how those work.
Thanks, Barry - N4BUQ
----- Original Message -----
From: "Dennis Tillman W7pF" <dennis@ridesoft.com> To: TekScopes@groups.io Sent: Monday, November 16, 2020 12:15:11 AM Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"
Hi Chris, I don't expect any problems shipping this to Germany.
One correction: This offer is strictly between Peter Keller and individual members of the group. I did offer to act as the go-between because I thought there might be some interest and because I understood how "sensitive" our members are to price. I was also hoping this would give Peter some well-deserved cash as we get close to the holidays.
So I told Peter I thought I might be able to pass along 10 orders for his book. When he said OK I notified TekScopes. That was 36 hours ago. I have orders for over 50 of his books as of this moment.
This brings back memories of when I asked for small donations to pay Groups.io the annual fee for hosting TekScopes back at the beginning of the year. Somebody please remind me the next time I think up something like this to think twice about what happened the last two times I had a bright idea. :)
Dennis Tillman W7pF
-----Original Message----- From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of ChrisBeee via groups.io Sent: Sunday, November 15, 2020 8:47 PM To: TekScopes@groups.io Subject: Re: [TekScopes] Special Offer from Peter Keller to TekScopes Members: The Cathode Ray Tube, Technology, History, and Applications"
Hi Dennis, I would be more than glad if I could support the group buy and get a copy of Peter's book, many thanks for making this possible! My only concern is if you would ship to Germany too. I will send you a PM with my contact data. Cheers Chris
-- Dennis Tillman W7pF TekScopes Moderator
-- Dennis Tillman W7pF TekScopes Moderator
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