66 rca new vista

[timmy]

hey guys just a quick question i have a 66 rca new vista that i recapped but from day one when its turned on the screen lights up bright the way it should and sound is present but the picture is like all white and during about 20 seconds the picture fades in perfect. could this be a video output tube that is taking alittle longer for the heater to heat or lagging behind the other tubes. because i have had 2 of the same tubes and the same result testing and one would take longer to show a result then the other. call me crazy but was wondering... thanks

[Username1]

Its the charm of the older sets.... Unless you see smoke....!?!?! Then it's not.

[Penthode]

Originally Posted by timmy

hey guys just a quick question i have a 66 rca new vista that i recapped but from day one when its turned on the screen lights up bright the way it should and sound is present but the picture is like all white and during about 20 seconds the picture fades in perfect. could this be a video output tube that is taking alittle longer for the heater to heat or lagging behind the other tubes. because i have had 2 of the same tubes and the same result testing and one would take longer to show a result then the other. call me crazy but was wondering... thanks

I don't think it is the video amp delay heat up. Note the video amplifier tube drives the CRT cathodes and if the video amplifier conducted late, the CRT would be cut off.

Have you done a proper grey scale? Eg the screen controls minimized, and then the service switch, adjusting the screen controls for the barely visable lines?

Try measuring the CRT grid and cathode potentials when the set is switched on and as it powers up.

[timmy]

yep did it all the gery scale, the works, and the picture after about 20 seconds is amazing for the age. and the crt is from 1982, november so thats ok.

[old_coot88]

Sounds like he's saying the screen comes on all white, then it takes 20 seconds more for the pic to come in.

[timmy]

yes it does but you can see just a bit of a picture but it comes right on like a tube is taking longer then others.

[rca2000]

Maybe the Y amp is slow heating ? Would not that cause a delay of video...BUT allow "color" to be seen? Or some component in the Y amp ckt. I would chack the voltages on the cathodes at startup, AND after warm-up. Compare the two---and I BET you will see a major difference.

[Electronic M]

If the color is weak of absent too when this happens then it could be a weak/slow to warm up tube in the tuner or IF.