I think it will also help to understand what you wish to achieve. Do you just want to be able to test/review continental equipment without having to replace the plug in which case a Schuko socket strip with a 13A plug fitted would be sufficient? If you are trying to compare the effects of UK and continental mains supplies there are a lot of differences to consider including the use of lower rated three phase supplies to the continental buildings.

I do have a 1920s HMV wind up gramophone (bought by my brother and sister for a couple of shillings in the 1950s) together with a pile of 78s in the bedroom...when you look at it with an engineering eye it's actually a very neat bit of technology. And really quite good for explaining how sound waves work

Re vinyl and CD, I found this most interesting in the early days of CD players, to me they sounded dreadful whereas I didn't mind the pops and scratches of vinyl, other people were much more irritated by the background noise of vinyl but didn't mind what I could hear in CD players. The problem with the early CD players was that, if you imagine them playing back a peak-to-peak triangle wave, each "step" in the A/D process was likely to be of a different height to the next one - say the average step height across the 65,535 steps is 1uV, then in practice one bit step might be 0.1uV and the next 1.9uV (to take it to extremes). The manufacturers worked hard to makes sure that each step always went upwards, but they weren't necessarily even. Which produces a very non-musical (non-harmonic) distortion. Vinyl does also typically have distortion too of course, but it's more likely to be harmonic. But there you go, again it was a case of things that annoy some people and not others. And, at least to my ears, got resolved in reasonably priced CD players by the end of the 1990s.

And then of course currently one of the biggest selling formats is the compact cassette which, pure audio wise, has to be one of the most appalling formats ever developed. (Although a very clever bit of technology for its time.) Just like I do have a much loved two-valve guitar amp behind me...

Re small speakers, what they can't do sadly is move enough air to project bass sounds at any distance. (OK, you can combine lots of small speakers, but that's really the same impact as having one big speaker.) Frustrating point at the moment as I've been playing quite a bit of bass guitar in otherwise acoustic bands recently, acoustically the only solution would be to move to double bass (which are both massive and really hard on the fingers for a very good reason) or to carry a bass amp. And even though I have about the smallest one it's possible to get (that's of any use) it's still a lump. It does feel like there are times when you just get hit by the laws of physics, but it would be great if somebody did come up with a cunning way of slowly moving lots of air without needing lots of weight / size! I'll keep hoping.

Contact made 

mapj1 said:

Not all of them - by the late 70s I was repairing the odd radiogram, well, valve swapping and doing basic 'wire off' and switch cleaner  type repairs anyway, when the shops would no longer repair them.

I did the same with televisions. They could be had for 10/-, which soon became 50p. The CRTs were faded so the curtains had to be shut, but with luck one lasted for 6 months.

mapj1 said:

Rather like some folk look nostalgically at old houses and say 'they built them well back then' what they mean is they built the ones that are still here now, well, back then. The slum grade stuff has been bulldozed and rightly so.

Most of my 120 y.o. house was built well, but it has become apparent that there was extensive refurbishment circa 1982. The real problem was lack of maintenance and ivy growing up the walls. At which point, young folk will ask, "What is maintenance?"

Andy Millar said:

And then of course currently one of the biggest selling formats is the compact cassette which, pure audio wise, has to be one of the most appalling formats ever developed.

More convenient than reel-to-reel, but you were lucky to hear both sides without the tape wrapping itself around the rollers. The great thing was portability (better than a wind-up gramophone) and you could get one for your car.

P.S. I still have a valued car radio (wireless?).

Chris Pearson said:

I did the same with televisions. They could be had for 10/-, which soon became 50p. The CRTs were faded so the curtains had to be shut, but with luck one lasted for 6 months.

Makes me think of the time when, part way through a job / house move, my wife and I were living at opposite ends of the country for a while. On a phone call one evening she told me the television had stopped working, so I told her to give it a hard thump on the top. Took a while for her to believe me, but in the end she did, went way for a moment, and came back and told me with great surprise that it had fixed it. She then asked me what to do if that didn't work, and I told her you thump it on the side instead...eventually I'd have to give up and remake all the solder joints on the CRT base.

I also explained that I knew this from my degree in electronics. What I didn't say that it was nothing to do with the course, it was because of having no money while I was a student, and so we learned this to get our junk shop televisions working!

Have you ever tried turning a colour CRT TV upside down? It's highly entertaining what it does to the colours (mostly, doesn't work on all, e.g. Sony Trinitrons you could turn upside down). Took me ages to work out why...used to be a good way of winning a pub bet against engineers who thought they knew about TVs. 

I also explained that I knew this from my degree in electronics.

ah I can't say that as I never had a degree in electronics ;-)   But I do have one in physics specializing in solid state and EM..

In a way it is a great shame that for many folk there is an imaginary ' I cant do that' divide between the practical and theoretical. A few hours fixing domestic electronics teaches you a lot that is not on any course, about oxide layers, what happens where fluff and grot build up, and also not to be afraid of any table top fire you that can extinguish without getting out of your seat.

In reality I reckon 9/10 repairs were just mechanical - needing little more than re-soldering, switch cleaner, and a bit of wash and brush up. Apart from those wirewound resistive droppers to get the series heater voltages to add up to 230V  that used to go open circuit so often I had spare resistors to spot solder across the failed sections.

Radios and TVs from households with smokers were the ones needing the clean up the most.

I have boosted the heater volts to up the emission on a failing CRT a bit. It is all a bit bangernomics, as it shortens the life, but if its on the way out anyway so what.

M.

Have you ever tried turning a colour CRT TV upside down? It's highly entertaining what it does to the colours (mostly, doesn't work on all, e.g. Sony Trinitrons you could turn upside down).

Sounds like "experiments" I did with permanent magnets and colour TV tubes when very young... which was entertaining until I found the effect didn't entirely  go away when the magnet was removed (for which I was in trouble as it was the family TV..) Eventually I found I could degauss the affected bit of the shadowmask with a transformer borrowed from something else.

   - Andy.

mapj1 said:

for many folk there is an imaginary ' I cant do that' divide between the practical and theoretical. A few hours fixing domestic electronics teaches you a lot that is not on any course

I find in particular about design for real world reliability and serviceability - which can be a difficult balancing act: every connection degrades reliability, but adding pluggable connections improves serviceability. My post graduate training was at the BBC in maintaining a mixture of domestic, semi-professional, and professional audio equipment. Really interesting seeing the difference - what moved equipment into the firmly professional sphere was that it was designed to be modular and with really high quality connectors so that it was both reliable and serviceable. Having been through that really makes you think about your own designs carefully. Anyone who describes a Ferrograph tape recorder as "professional" hasn't tried taking one apart..

We also sometimes struggle in the rail industry explaining to new design engineers how to think about designing equipment that might need to survive of 40-50 years in a pretty nasty environment - again, experience of trying to repair such equipment is a good object lesson. (Actually, a very surprising amount of the sound equipment I designed in the 1980s is also still out there being used, every so often I go on to the various forums to help people keep them going, which is also good for the keeping the soul grounded! Again mostly switch and connection problems, plus of course electrolytic capacitors. Also oddities like rubber sleeving disintegrating.)

Also I find studying the best domestic equipment design (i.e. taking it apart to see how it works!) can be a good lesson in simplifying design. Back to the TV lab, the flyback circuit of transistor based CRT TVs I always think is an object lesson in how to design an incredibly complicated function using about four simple analogue components....nowadays you can make pretty much any function by throwing processing power at it, the fun of analogue design used to be trying to use as few components as possible!

Andy Millar said:

Have you ever tried turning a colour CRT TV upside down?

At my age! Mine weighs 38 kg.

AJJewsbury said:

which was entertaining until I found the effect didn't entirely  go away when the magnet was removed (for which I was in trouble as it was the family TV..)

And we did have a similarly embarrassing incident with a BBC monitor! Which I'd forgotten about until now...actually I think the problem there was that we tried degaussing it while it was upside down...and as you say it was never the same again. So it got pushed far back to the back shelf of the store room...

The effect (typically all the colours seem to drain downwards) is apparently partly due to the position in the earth's magnetic field, but I found mainly due to the fine calibration magnets typically being on slightly "dangly" supports which of course droop the other way when it's upside down.

AJJewsbury said:

which was entertaining until I found the effect didn't entirely  go away when the magnet was removed (for which I was in trouble as it was the family TV..)

And we did have a similarly embarrassing incident with a BBC monitor! Which I'd forgotten about until now...actually I think the problem there was that we tried degaussing it while it was upside down...and as you say it was never the same again. So it got pushed far back to the back shelf of the store room...

The effect (typically all the colours seem to drain downwards) is apparently partly due to the position in the earth's magnetic field, but I found mainly due to the fine calibration magnets typically being on slightly "dangly" supports which of course droop the other way when it's upside down.