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Old 14th February 2018, 07:17 PM   #41
LeftHandFool is offline LeftHandFool  United Kingdom
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Originally Posted by Tubelab_com View Post

Fed by a bench power supply capable of 1.7 amps at 650 volts continuously, the PC board got traces burned off, the resistor vanished, and the OPT is now a magnet.
Ouch! I had similar, if less clamitous troubles the other week when, whilst fixing my Leslie cabinet, I mistook the schematic symbol for a thyrister for a diode.
On the up side, now I know what a thyrister is .

Also, the smell of a burning, 40 year old, carbon comp resistor is also strangely pleasing, or is that just me?

Matt.
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Old 14th February 2018, 10:17 PM   #42
Gnobuddy is offline Gnobuddy  Canada
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Originally Posted by LeftHandFool View Post
Has 'cheap as chips' not made it across the atlantic?
Matt.
I've lived in Asia, Africa, the land of Trump, and Canada, and grew up reading a lot of books by British authors. So at this point in my life, my head is full of a jumbled polyglot of different spellings, different words, different popular phrases, and terminology from many decades.

So is it "valves" or "tubes"? Tyres or tires? Checks or cheques? Metres, or meters, or feet? Should we measure velocity in metres/second as scientists do, in kilometers per hour as most lay people do, or in fathoms per fortnight (as some Americans would probably prefer, simply to be as different from the rest of th world as possible)?

I'm thoroughly confused, in other words!

-Gnobuddy
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Old 14th February 2018, 11:11 PM   #43
PRR is offline PRR  United States
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Originally Posted by Gnobuddy View Post
....fathoms per fortnight...
That's absurd.

Furlongs per fortnight makes sense. (2fps, or 1.34MPH, a very gentle stroll.) (About the speed I was walking last year.)

Furlongs were nominally OK in the UK until the Weights and Measures Act of 1985.

Last edited by PRR; 14th February 2018 at 11:13 PM.
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Old 15th February 2018, 12:40 AM   #44
LeftHandFool is offline LeftHandFool  United Kingdom
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Furlongs were nominally OK in the UK until the Weights and Measures Act of 1985.
Is that so. These days, the furlong still crops up as a measure in horse racing. To the best of my knowledge, the Weights and Measures Act dictates the size/quantity of a measure of ale/spirits. In which case, a furlong of ale for me....

Matt.

Ps. it occurs to me I may be confusing the weights and measures act with something else. Regardless, I still want a Furlong of Ale...
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Old 15th February 2018, 01:00 AM   #45
LeftHandFool is offline LeftHandFool  United Kingdom
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Originally Posted by Gnobuddy View Post
I've lived in Asia, Africa, the land of Trump, and Canada, and grew up reading a lot of books by British authors. So at this point in my life, my head is full of a jumbled polyglot of different spellings, different words, different popular phrases, and terminology from many decades.

-Gnobuddy
I embrace wholeheartedly the differences between the 'Queens' English and that of the English language spoken elsewhere in the world.

Every variation represents a possible new entry into the OED, and even where one fall short of official recognition it still represents a new word to add to our shared vocabulary.

A shared language leads to a shared culture, I'm all for that, although by no means do I wish to suggest the English language is the only means by which to share a culture.

I'm on the borderlines of politics here so I'll say no more, except that as an eleven year old boy - in a Disneyland gift shop, on holiday in Florida - I'd never have asked the price of the Mickey Mouse 'Rubbers', had I been aware of the language barrier...

Matt.
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Old 15th February 2018, 07:21 AM   #46
Gnobuddy is offline Gnobuddy  Canada
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Originally Posted by LeftHandFool View Post
I still want a Furlong of Ale...
How about a firkin of ale instead? That used to be a legitimate unit of beer at one time...

-Gnobuddy
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Old 16th February 2018, 06:35 AM   #47
PRR is offline PRR  United States
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Originally Posted by LeftHandFool View Post
...the furlong still crops up as a measure in horse racing. To the best of my knowledge, the Weights and Measures Act dictates the size/quantity of a measure of ale/spirits....Ps. it occurs to me I may ...
Weights and Measures Act 1985

It starts by defining Yard and Pound in french units (I thot this was old news??) Then it specifically says "shall not remove the pint", which would affect your drinking. (Gee, even in the US we drink by the liter.)

In Myanmar, highways are marked in mixed miles/furlongs. (A remarkable precision-- here if the exit is 284-1/4 miles down the road, we round-out the 1/4 mile. Do they have furlong odometers?)

Yes, horse-racing changes slowly. Australia went over in 1972 but UK US Canada and Ireland cling to the old lengths. There are multiple definitions of furlong, mostly too small to matter to anybody avoiding the metric system. Toronto was laid-out on a 10 furlong grid, which now appears as a near consistent 2km between highway exits.

Authority for furlongs per fortnight.
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Last edited by PRR; 16th February 2018 at 06:38 AM.
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Old 16th February 2018, 07:02 AM   #48
PRR is offline PRR  United States
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Originally Posted by Gnobuddy View Post
How about a firkin of ale instead? That used to be a legitimate unit of beer at one time...
A lot to drink at once. Basically "a keg". 11 Gallons/44L, give/take a brewer's exactness.

The subject came up here. Beer is often advertised by the pint. Someone thought his pint was short. This is indeed, on the face of it, a matter for the Bureau Of Weights And Measures. Who got involved. For a while it looked like all the pubware would have to be scrapped, and new calibrated glass with a line on the side bought. Which works out to much more money than the alleged shortness. Eventually the idea sank.

I can see it for gasoline pumped right into your tank. You never see it, and you can't be sure you got every drop charged. But a pint of beer, you see it, generally before your money is taken. You can speak up then. Or you can drink it, and decide it was not worth the price, go down the street to another pub with more generous drafts. Or to the beer/bait shop, buy BUD which is always the exact amount marked on the can.

And yeast-water is cheap. You say you like the taste but the real "product" is the alcohol. Do these pubs and small craft brewers have to proof-test to be sure their product is 5.5% as claimed? (There was a converse controversy: some craft beers were brewing significantly stronger than their nominal %.)
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Old 19th February 2018, 02:00 AM   #49
thoglette is offline thoglette  Australia
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Originally Posted by PRR View Post
And yeast-water is cheap. You say you like the taste but the real "product" is the alcohol. Do these pubs and small craft brewers have to proof-test to be sure their product is 5.5% as claimed? (There was a converse controversy: some craft beers were brewing significantly stronger than their nominal %.)
It's interesting to me: I can find good tasting ales in the UK that are +/- 4% but I struggle to find them elsewhere in the world (often beer with the same label ends up at 5.5% when packaged and exported).

Germany also seems to be able to make a decent tasting medium strength beer: e.g. a Düsseldorfer Altbier is inevitably shy of 5% and yet full flavoured and complex.

Finding a near-beer (sub 1%) with taste definitely requires a trip to Germany.

The current fad for 7%+ dry-hopped IPAs just does my head in. In every sense!

Meanwhile, back on topic, has anyone an opinion on Tristan's Merlin High Gain Preamp mated to a SE beam tetrode?
Is that cutting of one's nose or is it creamy-tone city?

Last edited by thoglette; 19th February 2018 at 02:04 AM. Reason: Meanwhile, back on topic
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Old 19th February 2018, 02:36 PM   #50
LeftHandFool is offline LeftHandFool  United Kingdom
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Default Layout question.

Afternoon all,

A quick question regarding layout:

From the perspective of keeping noise out of the circuit, do I need to locate the anode (load) resistors as close to the anode as possible, or am I ok to mount these resistors in a sub-assembly elsewhere on the chassis?
Obviously, the wire(s) which then connected the sub-assembly to the respective anode(s) would need to be sympathetically routed.

I think I'm right in saying that most of the noise in a valve is generated by the grid stopper, and that the first pre-amp valve is also largely responsible for the overall noise level.
The grid stoppers will be soldered directly to the valve sockets, using screened wire between the input and the first gain stage.
Board space is limited, and relocating some components to another part of the chassis would help the design flow. The anode resistors seem a likely candidate. Am I missing something?

Matt.
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