Audio Generator or Function Generator? Which to get?

Mar 13, 2017 70 Replies

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I doubt it managed 50%, let alone 0.5%. It had 3 outputs, sine square & tri angle. At some frequencies one output looked more like one of the others sh ould, and the others were just a mess. It was dire, and yes I followed the advised circuit. It might manage 0.5% at some frequency, but as a sig gen i t was a real failure. If I ever get the time I'll look at it again one day, it's on a shelf somewhere.

NT

snip

It's certainly way off. Domestic valve gear typically runs a couple of decades before needing a new valve. TVs weren't as reliable, being expensive goods in their time the valves tended to be pushed harder & the TVs ran hot.

NT

Surely that beats a dumbed down retardopedia. Some topics just aren't that simple. There's always the simple-wiki articles aimed more at children. Wiki has its problems, but I'm not convinced that is one of them.

NT

Right that's my memory, I could tweak one up and get the 3rd harmonic down below ~1%.. but not by much. BTW I've got tubes of ICL8038's if anyone wants to play with some, drop me an email. (Well US/Canada... shipping costs.)

George H.

TV's also had more tubes. So with the same mtbf per tube, the system reliability was much less.

Dan

I may not be an expert in various areas of electronics and computers, but I am far from a novice. There are various electronics related pages on Wikipedia that I can't read without going to the references and studying. That is ridiculous.

When only the experts in a field can even read and understand an encyclopedia entry I'm not sure that's any better than a "retardopedia". It essentially becomes the same thing, a web page that conveys very little information to very few people.

I think the editors end up being full of themselves trying to be "expert" or "professional". In the end they become irrelevant.

Rick C

He wants to do a listening test. You know, with the ears. How many of us can even hear 0.1% distortion?

Rick C

again mtbf was not the same. This was common knowledge in the valve tv era.

NT

I don't recall seeing such pages. There are some idiotic ones, wiki certainly has its problems with wallies thinking they're experts. But for an encyclopaedia I don't know a better one.

NT

It looks good, doesn't it? The Agilent had a knob, that controlled one digit at a time of the frequency (so it would give you a step on dialing). The multipurpose 'knob' of a DDS gets so many functions assigned to it... just spend a minute or two in the menus, and you can attach the knob to the 'frequency' attribute. First, though, just a minute or two in the menus, and you cn attach it to the 'amplitude' attribute. Before that, of course, you gotta power the gizmo up and give a few seconds to boot, and squint at a few menus to make sure it's not simulating heartbeats, 'cuz you want a sinewave.

On a test bench, you want to power ON, adjust volume to see a meter move, or hear the speakers sound off. Then you check the frequency range, and turn the F dial... all of which takes four seconds. Total.

Yeah, so? I can't fix my flat tire with a hammer either.

Rick C

** See page 20 of the pdf.

You are so full of s*it.

It had 3 outputs, sine square & triangle. At some frequencies one output looked more like one of the others should, and the others were just a mess.

** Meaningless bollocks.

Your only area of expertise.

.... Phil

** More meaningless bollocks.

Valves have a useful life of only a few thousand hours - less if abused.

.... Phil

Page 20 of a 12 page pdf? Page 2&3 quote 0.05-1.5% distortion, which may well be true for some of the scale. But twiddle the knobs and it went off the chart.

Baseless abuse is your area of expertise. You don't even know the facts.

NT

horse crap. I've run them way longer. Those lifetimes applied to early bright emitter valves - they've come a whole long way since then.

NT

** Should be "see figure 20".

** Thoroughly fact based, fair comment.

You are a prize bullshit artist and nasty piece of work to boot.

.... Phil

** Meaningless crap.

You are using fake facts.

The only kind you ever have.

.... Phil

Mfr admits to 11% distortion. We got way worse.

A sensible person would ask why might it have produced so much distortion. A sensible person might ask if I'm likely to get the time to find it, repair it & demonstrate its problem.

Oh. I suspect quite a lot of people think that one more fits you. It doesn't fit me. You think it does, but know not a lot about my life.

If you have electronics knowledge to contribute, great. But when it comes to stupid & abusive comments, why bother.

NT

of

sed.

No, it has a definite meaning. I've run valve kit for years without valve f ailure.

Well here's the first random search result

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... it doesn't agree with you either.

Then you could apply a basic common sense sanity check. Filament lamps run around 1000hrs, which is what bright emitters were. They were run at lower temperature to prolong life, so you'd expect a few thousand hours or therea bout. Dull valve emitters managed 1 or 2 orders of magnitude more than brig ht. Fluoresent tube emitters managed 10k hours decades ago. TV tubes ran fi ne for a decade or so left on all day every day.

But hey, maybe there's a large number of us that share the delusion of runn ing valve gear on a heavy use basis for many years and having very few fail ures. Or... just maybe... your knowledge isn't quite as thorough as you thi nk.

Come back with some real facts. And if we're really lucky, a sensible attit ude.

NT

tabb...is a lunatic and a liar

** Massive, blatant lie.

** Nothing in there proves a damn thing.
** Must be a delusion - cos it contradicts the experience of all others.

Or just plain old bullshit made up by valve freaks.

I told you to f*ck off.

Do so or I will hound you off this NG.

..... Phil

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