Is there a such thing as a reliable tube color TV? - Videokarma.org TV - Video

***Kamakiri*** · #1 09-13-2013, 11:50 AM

Yanno, between nearly impossible to solve convergence issues, replacing 6GH8s about every other hour, horrible purity, bad picture tubes, yokes that fall apart due to brittling from heat....not to mention the tedious restoration process and the de-cataracting of picture tubes, are there any tube color sets that can be made to be reliable in 2013?

Reliable, not as in when they were new, but well built enough to be made to be reliable today.....

Username1 · #2 09-13-2013, 12:24 PM

get an early 70's Zenith.

DaveWM · #3 09-13-2013, 12:28 PM

zenith sets are prob the most reliable IMHO. they often work with no restoration needed what so ever. I have several both roundies and rectangles that are very reliable. They also have CRTs that have bonded screens that while may turn a light green around the edge, are still watchable without removing the lens.

oh one more thing, if you really want to use it a lot, putting a fan in it to help keep cool may help with long term relialblity. I added a fan just for this reason to my CTC-5.

6GH8cowboy · #4 09-13-2013, 12:51 PM

In my days in the biz, Zeniths seemed to be fairly reliable but the pix didn't always offer a good color rendition of facial tones. RCA's could do very well but I think RCA was making up for lost time and money to recoup for the cost of color development that ran soooo over what was expected. Quality in production could have been better. Dumonts and Admirals had spectacular color but were less tollerant of differences in cameras and stations back then.

Today we fix, tweak, craft, rewire, scrounge, and sometimes talk to sets that were never reasonably expected to last 50 plus years.

We are Jug Heads! It's what we do.

***Kamakiri*** · #5 09-13-2013, 12:55 PM

Quote:

Originally Posted by 6GH8cowboy

In my days in the biz, Zeniths seemed to be fairly reliable but the pix didn't always offer a good color rendition of facial tones. RCA's could do very well but I think RCA was making up for lost time and money to recoup for the cost of color development that ran soooo over what was expected. Quality in production could have been better. Dumonts and Admirals had spectacular color but were less tollerant of differences in cameras and stations back then.

Today we fix, tweak, craft, rewire, scrounge, and sometimes talk to sets that were never reasonably expected to last 50 plus years.

We are Jug Heads! It's what we do.

Incidentally, having attempted to watch both a CTC-25 and a CTC-36 on a regular basis, I now understand your username.

I might change MINE to 5GH8cowboy

***Kamakiri*** · #6 09-13-2013, 12:39 PM

I kind of figured that, so I bought a Zenith roundie recently in working condition, semi-restored. Worked for about two minutes when I got it home, picture started to shrink from the bottom, and I started to smell something. Shut it down. What a let down. I'll get to that once I get the customer work done.

RCAs, though, I have zero luck with.

I guess you can call this thread a "rant". Your support and commiseration is appreciated

DaveWM · #7 09-13-2013, 12:52 PM

well it will prob be something simple.

a few things I always do, pull the horz and vert out, do a slow power up while monitoring the AC line currrent (metered variac) and the B+ and temp of the filter caps.

I theory is this will give a cap time to reform (if its going to reform) and will also quickly let you know if there are any shorts in the B+.

Pulling the horz and vert is just done as a preventive measure in case the low voltage prevents osc and bias issues on the tube.

Typically I will let this process go on for several hours starting at about 10vac and working up to about 80vac, as long as the B+ seems ok and nothing starts to heat up.

My guess on yours is a shorted filter cap followed by a smoked resistor in the filter network.

I did have a zenith with a shorted disk cap but that was an easy fix and the only thing that was wrong with it. I did not even pull the chassis, just replaced it with the service saver chassis cover removed.

Good luck with your zenith

truetone36 · #8 09-13-2013, 01:12 PM

As a CTC-25 owner myself, I can relate to this.

***Kamakiri*** · #9 09-13-2013, 01:29 PM

I lost all color on my CTC-25, had a perfect black and white picture. Come to find out that two 6GH8s are SHORTED, replaced them, and now I have a purple band at the top, a green band at the bottom, and white in the center. Screen looks like a "Mystery Mix" Now & Later candy.

Yay.

DaveWM · #10 09-13-2013, 01:34 PM

I wonder if using 6U8's or 6EA8's would increase the reliability of sets that have all those 6GH8's?

holmesuser01 · #11 09-13-2013, 03:30 PM

I've tried them. It's got to be the 6GH8's.

DONT use the International/Lindal brand. Some runs of the RCA 6GH8's were better than others. I've had issues with GE 6GH8's in the past.

Side note: I replaced the 6EA8 in my CTC-10 tuner with a 6GH8. It worked good enough to leave it in. That was years ago.

kvflyer · #12 09-13-2013, 04:41 PM

Quote:

Originally Posted by holmesuser01

I've tried them. It's got to be the 6GH8's.

DONT use the International/Lindal brand. Some runs of the RCA 6GH8's were better than others. I've had issues with GE 6GH8's in the past.

Side note: I replaced the 6EA8 in my CTC-10 tuner with a 6GH8. It worked good enough to leave it in. That was years ago.

Didn't RCA use Sylvania manufactured (labeled RCA of course) 6GH8 tubes in their sets later on because of the reliability?

zeno · #13 09-13-2013, 05:11 PM

As said a Zenith is the best tube color set to deal with.
With the steel chassis & hand wiring they just hold up best.
Even in the 70's we used to get RCA's & others that the PCB
& wiring was dried to a crisp. Never seen a Zenith dried up.

We used to buy 6GH8's by the gross about 3 times a year
from Zenith for 90% off. Nothin but problems no matter
what brand. With RCA's you also got to watch the tube
sockets, changed tons especially the pair up front. 5GH8's
were used in that first all tube 19" plastic RCA. I despised
that chassis, gave a nice pix but always needed an arm full of
tubes for the little problems. Too much heat I suppose.
So try a Zenith, at least when it craps out it wont turn to
dust working on it. & add a fan to anything..........

73 Zeno

***Kamakiri*** · #14 09-15-2013, 08:21 AM

Quote:

Originally Posted by zeno

5GH8's were used in that first all tube 19" plastic RCA. I despised that chassis, gave a nice pix but always needed an arm full of
tubes for the little problems.

Um, YUP.

On my CTC-36, replaced 4 5GH8s on the first go round. After testing the rest of the tubes, it needs one more. Along with the 24LQ6 (nearly dead), 5AQ5, 3KT6 (weak and shorted), and 6HL8.

By the time I get done sourcing and buying these tubes (everything I have is too old, I spent an hour rummaging through my loose tube boxes), I will have replaced every tube in the set, aside from the 3A3....including the picture tube.

This is the way these sets were when new? Holy hell, it's a wonder anyone that owned one ever bought another RCA!

jr_tech · #15 09-15-2013, 12:09 PM

Quote:

Originally Posted by Kamakiri

This is the way these sets were when new? Holy hell, it's a wonder anyone that owned one ever bought another RCA!

In my household, after the RCA CTC-22 it was all Sony Trinitron solid state sets... never looked back! Don't get me wrong, I love collecting and repairing the older sets, but they are not used for daily watching.

jr