Mono CRT display colour - UK Vintage Radio Repair and Restoration Discussion Forum

simpsons · 18th Mar 2019, 10:56 am

Having just read the excellent thread on bringing the 17" KB Imperial back to life, I was disappointed to see that the CRT display was predominately blue and not from memory, the “true” black and white display I had seen on KB televisions such as the KB Queen.

I also remember a Bush TV 12A restoration in which the earlier MW22-14 displayed in B&W whilst the replacement MW22-16 was again predominately blue.

Is this my imagination or was there a need to improve the display brightness which was traded off for a dimmer but technically more correct display.

Did manufacturers such as Brimar, Mazda, Mullard and soon have their “pet” P75 phosphor mix and was the choice driven by the TV set manufacturer?

regentone001 · 19th Mar 2019, 6:48 pm

I can remember years ago having two Regentone 10 - 17 sets side by side one showed a blue display and the other was a definite pink hue. I can't remember now whether they had the same make tube in or not but I have always remembered the difference in colour as it was so easy to see.
Steve

simpsons · 20th Mar 2019, 2:47 pm

Thanks Steve for that information on Regentone.

The pink screen that sticks in my mind is the Ferguson 988T which had a distinctly pink plastic implosion guard. I havent seen what the resulting picture looks like but unlike the early "add on colour" screens, I guess it wasn't trying to immitate the real thing.

But really, it is the imagined or real difference in brimar, Mazda and Mullard displays that interests me.

For example a MW 41/1 fitted in a Bush Chassis I viewed, seemed to be true black and white but without my tried and tested Minolta 2130 colour analyzer at hand, I had no reference to work from.

18th Mar 2019, 10:56 am	#1
simpsons Octode Join Date: Feb 2007 Location: Harrow, London, UK. Posts: 1,493	Mono CRT display colour Having just read the excellent thread on bringing the 17" KB Imperial back to life, I was disappointed to see that the CRT display was predominately blue and not from memory, the “true” black and white display I had seen on KB televisions such as the KB Queen. I also remember a Bush TV 12A restoration in which the earlier MW22-14 displayed in B&W whilst the replacement MW22-16 was again predominately blue. Is this my imagination or was there a need to improve the display brightness which was traded off for a dimmer but technically more correct display. Did manufacturers such as Brimar, Mazda, Mullard and soon have their “pet” P75 phosphor mix and was the choice driven by the TV set manufacturer?

19th Mar 2019, 6:48 pm	#2
regentone001 Heptode Join Date: Sep 2014 Location: Coventry, West Midlands, UK. Posts: 519	Re: Mono CRT display colour I can remember years ago having two Regentone 10 - 17 sets side by side one showed a blue display and the other was a definite pink hue. I can't remember now whether they had the same make tube in or not but I have always remembered the difference in colour as it was so easy to see. Steve

20th Mar 2019, 2:47 pm	#3
simpsons Octode Join Date: Feb 2007 Location: Harrow, London, UK. Posts: 1,493	Re: Mono CRT display colour Thanks Steve for that information on Regentone. The pink screen that sticks in my mind is the Ferguson 988T which had a distinctly pink plastic implosion guard. I havent seen what the resulting picture looks like but unlike the early "add on colour" screens, I guess it wasn't trying to immitate the real thing. But really, it is the imagined or real difference in brimar, Mazda and Mullard displays that interests me. For example a MW 41/1 fitted in a Bush Chassis I viewed, seemed to be true black and white but without my tried and tested Minolta 2130 colour analyzer at hand, I had no reference to work from.