DIY Electronics

Sorry, my bad typing:

"The last time we moved house he took all BUT a single sample of each type from dozens of brand new mains transformers."

That was 1992 so they're well-buried by now. Really nice countersunk transformers, too. 250v-0-250v, 6.3v, 5v - with a tap-changer plug on top. You could probably take a good guess at the application and of the valves involved..;}

PA

Not looking to sell .. happily give away

On 10/09/2021 16:25, Davidm wrote: interested.

I dont want to sell ... its free .... just seems a waste to dump it

JLH receiver and amp projects were the highlight of the project. Though this was when FM was seen as state of the art.

I'm not surprised.

Most stuff is ES now, and with LED a lot is non-replaceable at all.

I changed an F plug to a Co-ax plug last night for my neighbour's new telly.

I will give her credit for buying the new plugs (and for dropping a tenner in my toolbox)

Owain

Mine doesn't have a box (it's the local Nisa) but they have a self-serve machine that will do the printer for you (or if you buy it online, you just type a five-letter code into the machine and it prints out for you.

No extra charge, and it saves faffing with cutting and sticking lables out of A4 paper.

Owain

As an old timer and an ex Radio Ham operator from years ago, I started to learn a bit more about electronics during the first lockdown. From then I have managed to make or build a few small simple things that I could or can use. I have used breadboards for most of the things I have done but I have a soldering iron etc and have soldered some parts on breadboard size pcb's.

If you don't mind, I'd be grateful for some veroboard.

Just as an FYI

One of the guys here has taken all Vero board, IC's (liners & digital) and a whole load of transistors.

The 74 series chips must be worth a fair bit .... but I had no use for them, glad to pass them on.

Only just seen this but I'm pleased to say that our 10 year old knows about transistors and basic circuits. Snap Circuits kits seem to be the thing these days but some move on to breadboards and building from scratch. Our lad wants to build his own synthesiser - we've got as far as building oscillators so filters probably come next.

I'm into making valve amps, and most of the people on the valve newsgroups are 50-60, some older, a few younger. The average age on Hi-Fi newsgroups is the same. Kids these days are into computers and gaming rather than amplifiers and speakers. A lot use headphones. My son built his own computer but has no interest in audio electronics. It just has very little to do with his lifestyle. You may find the same thing with a lot of other kids.

Even the term "HiFi" is getting very dated.

It's more because it's about collecting music for background music appreciation, than anything involving. A 'greatest hits' compilation can be personalised and obtained with very little effort. Sonos is ideal for this. I prefer something else ...

A computer device (PC/mobile/tablet) does so much in replacing practically every other item of consumer electronics that used to sell in yr local Tandy electronics store.

Many youth have more interest in that, as the 150-in-one solution for everything else, plus getting hooked up.

It's quite a funny pursuit, find an online copy of a Tandy catalogue from the eighties, and think of the many ways that even a lowly smart phone works to make those individual items a redundant purchase.

From calculators, fax machines, answer phones, televisions, video recorders, cameras, camcorders, CB, game consoles, etc, etc....

One of the many reasons mentioned (stretching the point a little) why Tandy folded.

Excellent post Adrian, and many good points. I've never even heard of Sonos which dates me. And being a musician I prefer "difficult listening" to "easy listening". But I think you are doing youth a disservice to think they want 'greatest hits' compilations. They can be very choosy and knowledgeable about their music. My son gave me a 30 minute education in hip-hop which really opened my eyes. He's quite an expert on it and knows exactly what he likes and why he likes it. I was impressed, and hip-hop isn't something I ever listen to. Garage yes - I totally love Garage so I'm not growing old gracefully....

I think there's several things here:

One is that people aren't listening in a static place any more. That's why headphones are what they use. Just like computers went from desktops to mobiles, now audio has gone from separates to a phone and some Bluetooth headphones. There's no place for 'HiFi' in that world - it's all just DSP these days.

Another is that the price of property has gone up so much that people are getting their own place later, sharing with either their parents or other people well into their 20s or 30s. If you're living in a single small room there's not much scope for a fancy sound system that's only going to annoy everyone else.

Also, when all you have is a Spotify/etc stream, what you're playing is compressed audio to begin with. There's a limit to how much polishing you can do. (although the same could have been said of vinyl records...)

Finally, the quality of sound you can get out of consumer products like speakers and soundbars is very good these days. And, unlike past decades, they are cheaper to buy than you could buy the parts for. So not really any motivation to build your own.

One area that does seem to attract a certain class of youngster is in-car sound systems. But for them I suspect fidelity takes a backseat to volume...

Theo

The reality is that when I looked at the spec of an off the shelf class D chip - yes class D - 100W per channel too, it exceeded anything I could have designed back when I was designing audio amps.

In short there is nothing left to design. Back in the day electro mechanicals became the weak point - record and tape decks and moving magnet pickups. and loudspeakers.

Now we are digital, the possibility to do everything in digital, down to volume and tone etc - means that control pots only carry control signals, so that's an end to scratchy pots too.

All that is left is loudspeakers. I am halfway through refurbing a set of KEF bextrene coned units - and I googled around for what bextrene was, and why no one used it any more. The commonest answer was 'carbon fibre'.

Yep, at a stroke cones became lighter and stiffer than ever before.

In short, yesterdays 'hi fi' is comfortably exceeded by the meanest of digital chippery , and today's car hifi is probably somewhat ahead of any hifi speakers back in the day...

I was amazed when I picked up a 100 watt guitar combo I got cheap on ebay. Then I downloaded the circuit diagram. No iron in it anywhere. SMPSU. Class D amp, Fully digital tone and FX,

You can build valve for fun, but the cost of the iron is pretty prohibitive. I think I was up to around £200 for mains transformer, filter choke and output transformer before I even added in any valves.

I guess the next stage will be a optical socket in your brain and direct injection of audio into it.

Yep - me too! I still make 2a3 and 300b SE amps because I love the sound, but I know all the circuits so no challenge there.

So I've gone back to speakers, also with bextrene cones! Designing a 2-way with an aluminium cabinet. I love aluminium!

Once I've got some cabinets up and working I'll look into carbon fibre cones for the mid-bass, like you say. Nice.....