View Full Version : CRT TVs: turn on and off or leave on?


Dead Air
03-24-2009, 03:26 PM
Regarding CRT TVs (solid-state), is it better to turn the set off and on if not using it for 15, 30, 60, 120 minutes or to leave it on continuously? I know that saving electricity is important but does turning the set on and off many times shorten its life? My concern is primarily for sets from the 70's or early 80's.

I realize there are many individual factors as well as an overall effect which have to be considered:

-heating/cooling cycles of components and solder joints.
-heat which could dry out capacitors, crack insulation.
-degradation of the phosphor/burn in of the screen.
-does the filament or electrode of the electron gun get worn out?

Thanks for any insights.

MRX37
03-24-2009, 03:33 PM
Turn off, because when the CRT is on, it's aging, and the CRT will be the most difficult and or expensive component to replace. Yes, BOTH the phosphors and electron guns wear out.

zenith2134
03-24-2009, 04:03 PM
While I would not leave it running 24/7, it is better to leave it on if it's going to be used again in the next few hours.

Eric H
03-24-2009, 06:49 PM
If I was going to use it again in 30 minutes or less I'd leave it on, longer than that I'd turn it off.

zenithfan1
03-24-2009, 07:29 PM
OK, what about tube chassis sets? Same? I don't leave them unattended for more than an hour.

zenith2134
03-24-2009, 07:56 PM
What about falling asleep with tube-chassis sets on? I do it a lot.

site123a
03-24-2009, 08:01 PM
If I know I'm going to be away from my TV for more then 15 minutes, or get on the computer and not watch it, I turn it off.

I have an old 12" computer monitor that I had since 1994 that I still use, and I always turned it off when I'm not viewing it; The only problem I had with it was a soldering joint coming loose at the CRT socket about 2 years ago, but I'm pretty sure that happened due to age...

PS

Welcome to the forum.

zenithfan1
03-24-2009, 08:45 PM
What about falling asleep with tube-chassis sets on? I do it a lot.

If you've checked it and recapped it, no worries. It wastes some tube life at most. Just make sure it's getting plenty of air ventilation. I've done it too with these old beasts, I fall asleep in front of the restored '65 Zenith roundie in the living room. I would hate it if the plate voltage ran away on a HOT or something but I've been lucky so far. Knock on wood......

zenith2134
03-25-2009, 02:50 PM
I use my '66 portacolor in the basement, and a lot of times I'll lay down on the couch and fall asleep with it going...Hasn't been touched except the CRT is new. Probably not the best idea...:D

Richard D
05-06-2009, 11:46 AM
A friend of mine gave me Sony KV-5000 that had not been used in 15 years. I first powered it up on the 12VDC input so I could watch the current draw and adjust voltage. When I got to 13.5 volts it was working but with very poor contrast and dim picture. I left it running and worked on something else on the bench. About one hour later the picture had good contrast and brightness. The longer I left it powered up the better it got. The true test was the next day, at first contrast was a bit weak but within five minutes it was back up to a very good picture. Should I run this set a half hour per week? Have the Trinitron CRT rejuvenated with the risk involved or just use it. I am trying to find a 12VDC converter box for hurricane season to be kind to the neighbors and not run the generator so late into the night.
Thank's,
Richard

radiotvnut
05-06-2009, 01:05 PM
I wouldn't try to rejuvenate the CRT just yet. Many CRT's "die" from years of non use. They will usually bounce back on their own after extended use.

jpdylon
05-06-2009, 01:15 PM
trinitrons don't turn out well when blasting them with a rejuvenator.

Mark: If you want to add a little safety to your sets, you can install a fuse inline with the cathode circuit of the HO tube. The sams will usually tell you what the maximum acceptable value should be (like 220ma) I then install a acceptable fast-blo fuse in line with the cathode. That way if my HO fails it doesn't take the flyback with it. When the fuse opens in the cathode circuit the tube stops conducting.

Richard D
05-06-2009, 02:18 PM
Thanks for the advice. The more I use it the better it looks. I guess I could always get a small 12VDC inverter to run the dam digital analog converter box at night if we get hit with a hurricane this year. What really pi#@&^ me off is I have a nice mini and micro TV collection that of course will be useless during hurricane season.
Sorry for the rant,
Richard