EU survey on appliances and right to repair

For a thermionic valve, their specs are utter s**te. I had to suppress a cackle when I saw the 'reference circuit' using FETs as source follower buffer amps on both input and output sides of the single stage amplifier configuration. The FETs alone could have provided all the voltage gain needed without the inconvenience of that micro-miniature double triode 'chip' in the middle, thus making the device a totally pointless accoutrement.

Now, if they could fabricate a miniature twin anode beam deflection triode valve for use in HF receiver front end mixers to vastly improve intermodulation immunity to in band high power signals from other powerful transmitters broadcasting on aerials within 100 metres or so of the receiving aerial, then I'd go for one (or two?) as an Rx upgrade option.

Then again, maybe there's no need if the manufacturers have already come up with a solid state analog using FET/MOSFET technology. When I first heard of their use some 40 odd years ago, in radio receivers developed to cope with the multiband radio operations onboard WW2 battle ships, there didn't seem to be any obvious way to create a solid state version even though JFETS had started to become more common and CMOS was just making its first appearance in digital watch chips. For all I know, such devices may already be in use on board today's warships and in other military vehicles.

Well the job of explring the bowels of your pysche is done

And I thought you were old enough to have actually had a tube TV.

Obviously not, otherwise you'd not talk such s**te.

Its a wonder Russ Andrews hasn't cottoned onto replacement valves as yet;?...

Well we do have such receivers around like this one 'ere manages to sort out two signals 600 kHz apart wideband fM with a TX aerial doing 200 odd watts barely 20 feet away from the RX aerial...

what does that mean fact-wise?

NT

if you do develop the ability to read my mind some day I'll probably accept your apology. Sorry but telling someone what you think they think without knowing and insisting it's true is one of the stupidest things out there.

NT

VFD technology could be used just as cheaply to produce a many triode valve, making entire circuits doable with the valve, no trannies needed. It would be no challenge at all to include 20 or 30 valves in the thing.

NT

That's what I thought. There's no big deal in a double triode; they were common in the "old days". They could make a complete superhet radio in one envelope if they wanted to, so people could carry around a radio in a pocket! (Battery economy might be a problem though.)

I'm 42 so yes I have. And they were pretty damn reliable.

That they're crap.

More like "They didn't fall to bits in ways that were difficult to diagnose and nigh on impossible to repair, unlike the modern s*it."

Personally, I find modern TVs to be far more reliable than old valve sets, but to have a shorter overall life due to non-repairability - at least in an economical way.

SteveW

Strange, I know of zero tube TVs that had any fault at all under 10 years. But most LCD TVs fail after 5 years. Sometimes it's a capacitor you can change in the PSU, but half the time it's the screen that's f***ed.

Being able to diagnose and repair faults depends entirely on the skill of the individual.

They have a shorter life because they are cheaper, and many want the latest features.

On my first colour set which was a hybrid design, it was a near yearly task replacing the line output section. At considerable cost. And then a 'new' CRT after a few years. And then how many CRT sets did you ever see that didn't have registration and white balance faults? Modern sets are stable to a fault.

Anything unstable on a CRT I found could be fixed by adjusting all the little pots inside.

We have quite a good repair rate at public repair events. Most of the faults are in the power supply, and sometimes they can be repaired, or other times a replacement obtained.

I noticed the survey asked if TVs/monitors should have external power supplies, but unfortunately that would not solve this problem. These need many different power rails internally, typically ranging from 3.3V to 12V for the logic, and 600-1000V if they have cold cathode tubes, not to mention some which are on in standby mode, and others which are not. The external PSUs only generate one output voltage, which still goes through another power supply internally to generate all the voltage rails required.

No suprise you're talking s*it, but you need to evaluate more than just one persons experience.

It is possible to make an external PSU with more than one output voltage. Trouble is it usually coast a bit more and if a hight voltage is needed about 60V then there's more H&S to consider, adding to the cost.

That's why there used to be 1000s of TV repair shops around the country!