Is our view of old engineering distorted by the products which survive?

I'm not. Perhaps I didn't explain myself well enough, though. I'm particularly interested in what happens when spare parts are no longer available. My guess is that in the absence of spare parts, a modern TV will be impossible to repair, but an older TV may be repairable in the hands of a knowledgeable person.

Best wishes,

Chris

Interesting story, Don. Thanks.

Best wishes,

Chris

That toaster sounds very cool!

Best wishes,

Chris

Not words you hear every day! :-)

Cheers Trev

MIGHT be impossible to repair...

, but an older TV may be repairable in the

Possibly. I doubt if you can buy a new flyback coil, or even a CRT for a

70's television. Only a few types of tubes are manufactured these days, though lots of old tubes are still on the market.

Information is perhaps the biggest problem. I know! This is the "information age". But decades ago you could buy third-party service information for most any consumer television or radio on the market. That information (Mostly Sam's Photofacts) was in a standardized format and far superior to anything that the manufacturers provided. I doubt if anything like that exists today. Further, I believe that you will find that many manufacturers today consider their service information proprietary, and don't even release it!

Vaughn

The problem with Muntz TVs was that they could not be repaired. Most TV repair shops would refuse to touch a Muntz.

Joe Gwinn

Rebuild. That is the only way. Not new, but the gun and assembly is new. If the screen is crap - then it is a no-go.

Check into them.

Martin

Mart>> My guess is that in the absence of spare parts, a modern TV will be impossible

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But decades ago you could buy third-party service information for most

That is so true!

You'd have to go all the way back to July 2008.

And now you have to download repair information over the net! But seriously folks. If you have never seen a Photofacts package, please take the opportunity. They always did an incredibly good job of communicating.

The first time you see their cartesian component location technique you should be happily freaked out. I sure was.

--Winston

Ooops. But now you have a name/brand to google for.

The best ones were Blue Diamond, no longer made..the Ohios, still made, are better than nothing..but are sucky.

Gunner

It is. Way cool. Eric

Not because they were inherently unrepairable, but because they were crap. There was no way a service shop could end up with a happy customer, so they learned not to try. You woud probably get the same reaction if you took your Yugo to your mechanic for a tune up.

Vaughn

I stand corrected! Thanks

Vaughn

Some shops did work on them, but only on a time availible basis. They were crap when they worked, but the crappy design made it difficult to locate problems with common TV shop test equipment. I saw one in our shop, in the early '70s. The price of the repair parts was more than the set was worth.

From reading the articles from the time and after, they cut so many corners on the set design and construction to cut price that you had to have an intimate knowledge of how it worked to diagnose and fix it.

They took out stabilizing and buffer circuits to cut the tube count. They omitted most trimmer resistors and capacitors, they would trim in the circuit with a decade box and then solder in a fixed resistor instead of a pot - and you had to do it in a certain order, or you would affect the stability of other sections. Easy enough with all point-to-point construction with terminal strips and tube sockets. Back then, the labor was still cheaper than the components.

You didn't even get the basics like horizontal hold and vertical hold trimmers, unless a tech added them later to make the set work.

Muntz omitted extra RF amplifier sections and most filtering, figuring the set was being sold in strong signal areas only - which probably led to the obscenely high power levels used by the TV Transmitters on Mount Wilson, where there is no permanent population other than the technicians.

There are still areas up there where the RF levels are so hot at ground level you can light a 4' fluorescent lamp just by taking it out of the Faraday Cage of your car trunk.

-->--

He never intended them to be serviced, after the warranty.

Actually it isn't mush worse than the early reflex radios where a single amplifer was used for different frequnncies. The same tube was an RF and AF amp at the same time.

By the time the parts had aged enough to need adjusted, it was out of warranty. The schematics are in the old H. W. Sams Photofacts collection.

None of the circuits would have ever passed a design review.

Those mountaintop sites covered a large area, and the back side was shielded by the mountain. There is no way they would build a higher power site so people could use cheap YVs. The electric bill was always the biggest expense at most commercial stations.

One of those is gone. The okld VOA Bethany plant was so strong they could have lit everything with stray RF. Over 500 kW of RF in the 1.6 to 30 MHz range.

It's difficult to compare the two situations, I know, because the parts for the latest TVs are currently more plentiful. But would you rather be trying to fix a 1958 TV right now, or a 2008 TV in 2058? I'd go for the

1958 TV, because the electronics will be simpler with more discrete components, and so easier to understand. With many items of modern electronics, you're stuck unless you can get replacement circuit boards. I tried to fix a Sun computer power supply a while back, and it was a nightmare. I got it fixed for a month or two, but it was luck more than anything else. When it failed the second time, I just got another one.

Best wishes,

Chris

How did that work? Just measure along two axes?

Best wishes,

Chris

Now that I would like to see!

Best wishes,

Chris

I'm always impressed when people keep their old appliances going. I think we should be proud of that kind of philosophy.

Best wishes,

Chris