When did tv sets becamed more relaible and why?

[Telecolor 3007]

I guess more relaible tv sets camed out in the '70's. For 3 main reasons:
1) Imprvoing technology;
2) The Japanese wanted to show they can make better sets;
3) More tv programs - so people wanted to watch more hours without the tv having problems.

[Alex KL-1]

I believe that cumulated knowledge, too.
For example, when makers tried the germanium HOT, they promptly concluded that more reliable flybacks are in order, since germanium not cope very well with excessive voltage spikes (and Ge reduces maximum voltage ratings with temperature, hence enourmous dissipator needed for this function).
Even Si are more prone to fusing with sparks than tubes. Hence, better flybacks are in order.
And we are only talking about one part; in fact, capacitors are far better in end 60's when most makers abandoned paper capacitors when polyester caps become less costly.
Old 50's and 60's resistors makes more drift than the Fast and Furious Tokyo Drift drivers ;-)
And, for sure, much more reasons I believe...

[zeno]

Solid state sets were the reason. The first few generations were
built to last, no holds barred. In the early 80's the last great
sets were built & things slowly went down hill. You almost couldnt
by a "bad" solid state before that.

73 Zeno
LFOD !

[JohnCT]

Originally Posted by Telecolor 3007

2) The Japanese wanted to show they can make better sets;

There were a few Japanese tube TVs sold, but the Japanese started exporting into the U.S. in earnest about the time the switch to SS started. As a result, most Americans first experience with Japanese TVs were the SS variety, which gave them a big (and somewhat undeserved) reputation as high quality.

Even the best vacuum tube TVs required more or less regular repair. Once the SS TVs came out, the incidence of repair dropped dramatically regardless of who made the TV. Since almost all Japanese TVs were SS and the people who bought them were replacing an older vacuum tube TV, they assumed it was the "made in Japan" label that made them more reliable than the tube TV they replaced.

We sold just about every brand of TV there was, and even the low end Emersons were pretty reliable. Next to the Zeniths, Panasonics/Quasars, RCAs, Sonys, etc., they performed OK but couldn't match the picture, stability on marginal air signals, black level, etc. of the better brands. Even the remote control range was lower on the Emersons, but they were pretty reliable compared to other SS models and far more reliable than the tube TV they replaced.

I would say the domestic and imports were pretty neck and neck for reliability, but the one area that the domestics had an advantage was high hour longevity. When we sold TVs to bars, we pretty much kept them to Zenith and RCA unless they asked for a different brand specifically. Those boat anchors would run ridiculous hours for years on end with very little service required.

John

[Colly0410]

Here in England most domestic made sets were so unreliable that most people rented their sets so they had free repairs. My parents were renters until 1972/73 when they purchased a Sony KV 1800 that never ever conked out. It was still working perfectly in 1994 when my mother died & my sister had it, don't know what happened to it after that though. I bought 2 Toshiba LCD TV's in April 2008 & they're both working perfectly & never been repaired. Don't think England/UK make any domestic sets anymore, they're all imported AFAIK...

[JohnCT]

Originally Posted by Colly0410

Here in England most domestic made sets were so unreliable that most people rented their sets so they had free repairs. My parents were renters until 1972/73 when they purchased a Sony KV 1800 that never ever conked out. .

If they bought a Sony around 1973, then the TVs they were renting before that were vacuum tube TVs, which, regardless of who made them, required frequent repair between the natural degradation of vacuum tubes and the tremendous heat they generated which affected every other part in the TV. It sounds like your parents first SS TV was imported, which was my point.

Originally Posted by Colly0410

Don't think England/UK make any domestic sets anymore, they're all imported AFAIK...

Same here in the colonies. The last "domestic" TVs were from Zenith and RCA. The RCAs were still solid but Zenith had a lot of trouble with their CRTs.

My mom is 98 and spends most of her day in front of an Indiana built RCA rear projection TV (CTC/PTK195 analog chassis) that I gave her. This TV was built in or around 2001 and has never been repaired. I estimate the TV has over 70K hours on it. The CRTs are getting soft now and of course are showing pattern burns because she watches the same news channel most of the day.

I have a Sony 55" XBR in storage for the day the RCA quits (I won't fix it because the tubes are getting weak).

John

[Electronic M]

Originally Posted by JohnCT

If they bought a Sony around 1973, then the TVs they were renting before that were vacuum tube TVs, which, regardless of who made them, required frequent repair between the natural degradation of vacuum tubes and the tremendous heat they generated which affected every other part in the TV. It sounds like your parents first SS TV was imported, which was my point.



Same here in the colonies. The last "domestic" TVs were from Zenith and RCA. The RCAs were still solid but Zenith had a lot of trouble with their CRTs.

My mom is 98 and spends most of her day in front of an Indiana built RCA rear projection TV (CTC/PTK195 analog chassis) that I gave her. This TV was built in or around 2001 and has never been repaired. I estimate the TV has over 70K hours on it. The CRTs are getting soft now and of course are showing pattern burns because she watches the same news channel most of the day.

I have a Sony 55" XBR in storage for the day the RCA quits (I won't fix it because the tubes are getting weak).

John

You're confusing your eras in Zenith history.
Zenith stopped building TVs in the USA around 1980, and they had EXCELLENT CRTs in the made in USA era. It wasn't until the 90s when the sets were made in Mexico and Korea that the CRTs went downhill.

[JohnCT]

Originally Posted by Electronic M

You're confusing your eras in Zenith history.
Zenith stopped building TVs in the USA around 1980, and they had EXCELLENT CRTs in the made in USA era. It wasn't until the 90s when the sets were made in Mexico and Korea that the CRTs went downhill.

I consider the Mexican built Zenith and RCAs to be "domestic" as the chassis were identical to the ones built in Kentucky, Indiana, Chicago etc even as the ownership of both companies was transferred to overseas. Until LG started supplying Zenith with LG built product, Zenith TVs were still Zeniths.

The last RCA chassis made in Mexico were absolutely identical in every way to the Indiana built chassis - the only way of telling them apart was from the label on the back of the cabinet. The machinery was literally picked up and moved to Mexico, and since the construction of the chassis was all done by automation, there was no dropoff (or increase for that matter) of quality when the plants were relocated south of the border.

Mexico never supplied Zenith and RCA with home grown rebadged TVs (I don't know if Mexico even had that capability then).

Zenith tubes were still excellent through most of the 80s despite the movement to Mexico. The crappy Zenith tubes of the 90s were still built by Zenith regardless of what side of the border the plant was located. A Zenith engineer told me that Zenith had stopped making the gun assemblies themselves in the 90s and sourced the guns from elsewhere, probably Goldstar. It was Zenith's decision to outsource the guns, so I'm not inclined to give them a pass on this unless it was an LG directive. RCA was still making top quality tubes during the 90s, and Zenith should have had RCA/TCE supply the guns for them or just outright buy the tubes (there were actually a few Zeniths with 25" and 26" RCA pre-yammed tubes). The 31" inch and above Zeniths came with tubes not built by Zenith at all (I recall RCA, Toshiba, and Philips) and they were all good tubes.


John

[dishdude]

I didn't think Zenith made any CRTs in Mexico, I thought that plant stayed in the US and the tubes were shipped to Mexico for final assembly.

[old_tv_nut]

Zenith-made color CRTs were always made in Melrose Park, IL. as far as I know.

I know some CRT makers had guns built in Puerto Rico, but can't recall who - could have been practically everyone.

The various makers' moves to final assembly in Mexico also involved developing automated wood cabinet manufacturing so unskilled labor could do it. And later, consoles went out of style anyway.

[zeno]

Originally Posted by dishdude

I didn't think Zenith made any CRTs in Mexico, I thought that plant stayed in the US and the tubes were shipped to Mexico for final assembly.

Correcto
Zenith actually had 2 CRT's
1) Zenth Radio Corp / Zenith electronics EIA 343
2) Rauland Div of Zenith EIA 1101
Never knew why you could get either in a given model. I also had
a customer whos daughter worked for Rauland. It seemed to run independent
of Zenith, tax reasons ??
To my knowledge only built in the Chicago area. They only built
13" through 27" jugs. All other colors were sourced out.
Zenith Taiwan B&W sets used Clinton CRT's usually.

The Mexico plant was a disaster. We got 2 sabotaged sets. Both
;had wires snipped. Must have been just as the back went on.
The regional service mng came & took them. They were apx 1 month apart.
Just 2 really adds up with the huge number of dealers in the US.

73 Zeno
LFOD !

[Alex KL-1]

(Now I posted on correct thread):
Only for amusing, I only imagine perhaps a tube-based TV with modern resistors, capacitors and flyback/coils, with nowadays better stable mains, if reliability will be better than in it's days. At least for audio products, with modern parts, I can only need to change tubes when the tube are with problem, and not a problem caused by a bad resistor or (paper) capacitor cooking the tube (in the bias circuits for example). Of course, TV have far more tubes and resulting heat, but even so... (only for illustrating the contribution of passive parts)

[JohnCT]

Originally Posted by Alex KL-1

(Now I posted on correct thread):
Only for amusing, I only imagine perhaps a tube-based TV with modern resistors, capacitors and flyback/coils, with nowadays better stable mains, if reliability will be better than in it's days. At least for audio products, with modern parts, I can only need to change tubes when the tube are with problem, and not a problem caused by a bad resistor or (paper) capacitor cooking the tube (in the bias circuits for example). Of course, TV have far more tubes and resulting heat, but even so... (only for illustrating the contribution of passive parts)

Most decent vacuum tube TVs in the 60s and 70s had plastic caps and at least some metal film resistors although I remember some memorable early SS Sylvania chassis that used carbon comp resistors as voltage dropping resistors used to feed low voltage transistors circuits (the resistors got hot, dropped in value, dumped beaucoup volts into low voltage circuits where mayhem would ensue). EDIT: Could have been a hybrid in the D series. In any case, the signal circuits were all SS even if the sweep was hollow state.

Flybacks certainly could have enjoyed modern construction with epoxy and silicone instead of wax, but you would still need large(ish) value high voltage electrolytics which would still be problematic even today given the hours they would run and (as you noted) the ambient tube generated heat they would need to live in.

With regard to mains, vacuum tube equipment is more tolerant that SS stuff to noise and voltage spikes.

A modern built tube TV would definitely be more reliable in many areas compared to vintage stuff, but I'm not sure just how much more reliable a "modern" vacuum tube TV would be.

John

[Electronic M]

Originally Posted by Alex KL-1

(Now I posted on correct thread):
Only for amusing, I only imagine perhaps a tube-based TV with modern resistors, capacitors and flyback/coils, with nowadays better stable mains, if reliability will be better than in it's days. At least for audio products, with modern parts, I can only need to change tubes when the tube are with problem, and not a problem caused by a bad resistor or (paper) capacitor cooking the tube (in the bias circuits for example). Of course, TV have far more tubes and resulting heat, but even so... (only for illustrating the contribution of passive parts)

More stable mains?!? They're worse now than I remember them being as a kid. Noise, spikes/dips, outages I seen more of all the last few years than growing up.

The late 60s Zenith's with all film caps, silicone flybacks, and lytics not much different from modern ones (ignoring size) are about as you describe a hypothetical modern set, and are fairly long lived.

[zeno]

IIRC the Sylvania was a D-12. The resistors went between the 250V & 24V.
Caused quite a lot of havoc. Only other shorting resistors I remember were
in GE 18" compactron sets. It was in the video out left rear corner of PCB.
8.2 K 2W IIRC

As far as better tube sets go the first thing I would add is a cooling fan
near the Hoz/HV.

73 Zeno
LFOD !