Were there any all-valve PAL colour-TVs?

[Graham G3ZVT]

Originally Posted by Nuvistor

I never worked on one but when they came available I did ask why, presume Granada did rent them, perhaps they rented very well.

I don't remember them being popular, despite them being the cheapest colour set in the showroom.

The picture on them was very poor, I remember thinking to myself that I wouldn't have one as a gift.

[davyrocket2]

I think that i am thinking of a prototype version that used valves it was a ferguson a sort of forerunner of the thorn 2000 and I think think FERNSEH had mentioned it a post on here many years ago.I think i had been on show at either Olympia or earls court about 1965 - 66 ish

[kan_turk]

Thorn 1000 - not sure if that was an ‘official’ designation

[davyrocket2]

Hi. Sorry, BRC Thorn 2000 prototype as in a book called "The Set Makers".

[phut bang]

I still have a solid state Pinnacle PL802. I seem to remember buying it just to see what it was like. I think for a GEC CTV, well the TV has long gone and I kept this valve replacement just as history.

[vidjoman]

I visited an exhibition about 1966/7 at Mullard in Torrington Place where they showed prototypes from several manufacturers but I’m not sure if these were all valve.
I attended a lecture by Mazda about the same time about all the different types of colour tubes that had been invented. Most of the patents were owned by RCA who seemed to try and make sure they had a monopoly. They had a colour TV on show but I don’t know the make or whether it was PAL or NTSC nor all valve but I don’t think it was a Thorn 2000 prototype.

[Vintage Engr]

I worked on the very first colour TV's available to the public in 1967.
As far as I can remember, all the released U.K. manufactured sets were hybrid.

The Bush/Murphy range and the Baird, & GEC all used a plethora of valves, with generally just the decoders & sometimes audio o/p being discrete transistors.

I seem to remember the BF115 transistors in the Bush decoders being liable to fail frequently. We were always being warned about he X-rays from the PD500 shunt stabilisers, some of which had a lead - glass shield around them.

Some wag once commented that he wasn't sure whether it was better to wear it, rather that fit it over the PD500.. Generally, the valve sections were fairly reliable, it was the early transistors that failed.

I'm not sure how stable a reference oscillator at 4.43361875 Mc/s would have been...

Happy days!

Dave.

[ms660]

I remember the interlock for Xrays.

Lawrence.

[red16v]

Wasn't there a story that Dr Bruch's early experimental PAL sets couldn't handle a switching burst at the end and start of the burst blanking period in the vertical interval and that's why he invented his Bruch blanking sequence to get over this problem?

Seeing as how he would have been working on early prototype sets perhaps they were all valve?

[Welsh Anorak]

The G6 and the Baird 700 used valved decoders, though they were very different.
The G6's reference oscillator used a PCF802 and was pretty stable. It had some odd ideas, such as removing a valve to over-ride the colour killer in the dual standard set; this was removed in the single standard. This PCC85's heater was fed from a separate winding on the mains transformer so the set still functioned.
No PL802, but the familiar PFL200 was the luminance output. Unusually, the colour-difference drives were PCF200s instead of the usual PCL84s. This decoder was at least as reliable as most of its rivals, and fared better than some (hello Decca and Bush!). The dual standard pre-dated lockfits, but the single standard had them, though Philips had thoughtfully made the IF panel pluggable to help you replace them. The other panels were still hard-wired, though!
The solid-state PL802 was made by Pinnacle when the glass one was in short supply, and featured a vertical wirewound resistor to simulate the heater. The results weren't too good. LEDCo (nothing to do with LEDs) made a whole solid-state CDA panel for the Pye hybrid chassis when the original had turned to toast. Unfortunately the results weren't too good, and even worse, some resistors changed value and over-ran the CRT which expired very soon after. Not a great idea, especially as it had a thumping great dropper resistor on the top!
I don't remember the PCF200 having a solid-state replacement - was there one?
The G6 and 700 decoders gave their solid-state rivals a run for their money in performance and reliability. The Colourette, however....

[blakeyboy]

I moved into a rented house in the 1980's, and the landlord had thoughtfully provided a colour TV- a 26" if I remember...anyway it was massive, looked all valve, and the plate on the back said '400Watts', so it cost a bomb to run, and in the summer it cooked us.