Question about "Instant On"
 

Hello everyone,

My question is simple, if I have a cable box with a switched AC outlet, can I just let the box switch the set fully on and off? Or would it be better to power the box on first, wait a moment, and turn the set on with it's power switch?

Now the specifics...

The set is my 1971 RCA CTC-44A Trans-Vista console plugged into a Comcast/Motorola cable box with the switched AC outlet in back. I have been switching on the cable box first and then flipping the power bar on the TV after several seconds. When I'm done watching, I flip the power bar on the TV off first and then the cable box.

I didn't want to assume anything, since the set was designed to technically be "on" all the time....

Any thoughts or opinions are welcome and appreciated!

It's hard to advise someone on this.
Does the set have the original CRT? It's a great set, but well on in years.
If the CRT is original, it was probably used in the instant-on mode for several years of its life.
If so, I would leave the set powered on, all the time. Plug it in separately, instead of through the cable box.
I've seen owners do that with Zeniths. It seemed to take forever for the CRT to warm up. :yes:

The CRT is original, and it still has a nice bright picture. When I did allow the cable box to power it full on (the power bar on the TV was already flipped on), the picture comes up in about 7 seconds. I can see why advising someone on this can be tricky, as there are numerous factors to consider. I can't say for sure but from what I was told this set has fairly low hours, granted it was probably on the whole time slowly cooking the picture tube...

...

Thank you for the insight. Originally, my concern was if I just let the cable box switch it full on, something might fry in the set being that it was designed to be "on" all the time, I just didn't want to assume that it would power up like any other set. And I have heard the same thing regarding the CRT dying prematurely and certainly don't want that to happen, and I don't mind waiting a handful of seconds for a picture to come up...

You actually do NOT want the set to be in instant on mode continuously. This was a convenience feature which unfortunately shortens the tube life by running it continuously (though at reduced power). Instant-On was superseded by solid state chassis with quick-heating cathode CRTs, which could produce a picture in about 12 seconds (instead of, say, 50 seconds for an older all-tube set).

I don't think there is any detrimental effect from powering your set from the switched outlet, and it prevents the "slow cooking" from degrading the CRT over time.

Thank you for that as well. This is basically the conclusion I had drawn myself, but being NOT a professional in the field I figured there are no dumb questions (okay, I suppose there can be some dumb questions).....I only wish I could have been around for the heydays of this stuff. Let's just say my TV is about 13 years older than I am :D but its not stopping me from learning about, and collecting these wonderful electronics.

I have the same set. It also has a good tube...but not a SPECK of color. Anyway---I suspect that if this set is plugged in for at least 3 minutes and THEN you turn it on...the pix will cone up in about ONE second. Is this correct? Mine does.

You are absolutely right, mine will show a picture immediately after a couple minutes.

So why no color? Have you investigated that? Mine has excellent color but sometimes it will go green for a second or two and then flash back to normal. It hasn't been enough of an issue for me to tinker with it (yet).

I'm pretty much in the same boat, my favorite TV being 8 years older than I am. I wouldn't want to be older though, the only advantage of that would be having easier access to these sets when I started collecting.

i think your wrong with the shortened crt life. i seen plenty of rca and zenith with instant on that held up better than the warm up cool off crt's. it is not like they are producing a picture in instant start mode it is just reduced filaments.
you don't see a picture on the screen thus no electrons being produced by the crt

Cathodes do not work the way you assume. They are always boiling off electrons if hot enough, to create a "virtual cathode" that is the source of the electron stream, which is modulated by grid and anode voltages. If there is no net current, electrons are returning to the cathode at the same rate as they are leaving.

An old debate nobody ever won !
Personally IMHO instant on in an all tube set is a slow & painful
death of the rest of the set. Just a very bad idea. It dont matter if the tubes lasted longer or shorter.
On a solid state I dont care either way.
CRT's on Zenith flats lasted forever & RCA's did too. Most others
used GE, West., & Philco jugs didnt last but probably because of
the tubes & not the instant on.

73 Zeno:smoke:

True that the manufacture makes a big difference. Nevertheless, cathodes are always in the wear-out mode when on. Fewer hours on = more years of life.

Should note that in some cases, never turning on can have detrimental effects. The Saticon pickup tubes in our HD camera were supposed to be run for a few hours no less often than every six months, to counter the effects of residual gas in the tube.

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On your RCA CTC-44, the switches attached to the power bar have a habit of going bad - we replaced them in droves. I'd leave the set in the on position and use the cable box to do the power switching.

This assumes you have the 3" wide plated on-off "bar" switch. RCA called it a paddle, IIRC.

Cheers,

I believe it does have the bar. It is not plugged in at all--at the moment.

BUT---I DO plan on playing with it some more soon. To try and get some color out of the pix, and check the tube on my 70 too.

Mine has the bar. Its along the top of the panel just above the tuner knobs. And mine does have a little play in it. I don't know if that is the switch or the bar just needs to be tightened up.

The "on-off bar" on those RCAs was a bar attached to a pot-metal actuator that actuated two switches, much like those on the back of volume pots. We must have replaced a dozen of the actuators - toddlers liked to cycle them on and off, and some couldn't handle the stress. RCA never did upgrade the actuator to a better made unit. Instead, because of demand, they added the switch assembly to their "QT" (Quick Turnover) parts listing. I have one somewhere I salvaged from a junk RCA that got necked by some movers.

Of the two switches, one controlled the TV, and the other was for the instant on. Basically a diode across the open (off) contacts, passing half wave current to the filament of the CRT. The switch would fail (open all the time) with the symptoms of no picture, but HV was normal, or very dim pictures with the Brightness control all the way up. The diode would also fail (short) and put full voltage to the CRT. Good intentions, bad fail safe modes.

Cheers,

ON the 44? A diode in the fil. line? That is a cold set--I would not expect that to be the case. Maybe on a hot set--like a CTC-36, 41 or 53 or so...

IIRC_-the cold RCA sets with I-O--(which I think is all of the flat chassis sets by them)--had a separate filamant tranny, with a resistor in line with it and when powered on, a switch shorted the resistor and applied full voltage to the tube.