Re: Were there any all-valve PAL colour-TVs?
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....
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