The price of valves
Don Pearce
been reading a Wireless World from November of that year. Valves
(tubes for those across the pond) were extremely cheap. And
transistors cost pretty much the same, which is why we treated them
with kid gloves and thermal shunts when soldering them into circuits.
http://www.soundthoughts.co.uk/look/valves.jpg
Money conversion for the young and foreign:
20 shillings to the pound, 12 pence to the shilling. A price given as
5/6 meant five shillings and six pence. So an ECC84 at 6/6 is 32.5
pence in today's money. A 28012 transistor, by contrast at 140/- is
seven pounds - getting on for half the weekly wage of some people back
then.
I may post some ads for complete equipment later, just to make you
cry.
d
Ian Bell
I have some WW from 1940 to 46 - I'll see if I can find a camparison page.
Cheers
Ian
David Looser
news:hg5hgt$ok5$1...@localhost.localdomain...
1960s. There might have been a slight reduction, but not a lot. Of course
inflation was low during that time too. Transistors on the other hand
dropped dramatically in price and carried on doing so for a long time. An
article I have from a 1952 edition of 'Radio Constructor' refers to "some
(transistors) the writer recently obtained from the USA cost almost as much
as a miniature receiver". Whilst these days a bag of 100 BC548s costs but a
few pennies each.
David.
> Ian
Bob Eld
"David Looser" <david....@btinternet.com> wrote in message
news:7on3ivF...@mid.individual.net...
How about 450,000 transistors for $50 in a processor. That's $0.00011 per!
That level of integration makes our modern computerized world possible.
Imagine trying to do it with "fire bottles"!
Engineer
wrote:
> "Ian Bell" <ruffreco...@yahoo.com> wrote in message
Way, way back, I nearly cried when I fried an OC71 in an audio stage I
was trying to make!
Cheers,
Roger
Don Pearce
They were down to 5 Bob by 1966 - absolute bargain, particularly when
you scraped the paint off and used them for a photo transistor. I
first discovered this by accident when an amplifier I had made hummed
when I took the hardboard cover off the back.
d
Keith G
"Bob Eld" <nsmon...@yahoo.com> wrote
> How about 450,000 transistors for $50 in a processor. That's $0.00011 per!
> That level of integration makes our modern computerized world possible.
> Imagine trying to do it with "fire bottles"!
It didn't stop Tommy Flowers:
Brian Gaff
making valves got below a certain number prices started going up, and vice
versa for semiconductors of course.
I think one has to be careful if buying the Chinese copies of valves around
at the current time, as quality control is almost non existent, though some
Russian ones are made a lot better I'm told.
Brian
--
Brian Gaff - bri...@blueyonder.co.uk
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Don Pearce" <sp...@spam.com> wrote in message
news:4b273468....@news.eternal-september.org...
Brian Gaff
rejuvenators which claimed to be able to make television tubes work again
after they had gone low emission.
Then there were endless projects In Practical Wireles for things like Valve
ohm meters, and grid dip oscillators.
In some later television mags, when valves were being phased out, some
enterprising folk actually made valve replacements circuits using
semiconductors on a valve base!
As I recall, one flashover and they were history.
grin.
Brian
--
Brian Gaff - bri...@blueyonder.co.uk
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in the display name may be lost.
Blind user, so no pictures please!
"Ian Bell" <ruffr...@yahoo.com> wrote in message
news:hg5hgt$ok5$1...@localhost.localdomain...
David Looser
"Brian Gaff" <bri...@blueyonder.co.uk> wrote
>
> In some later television mags, when valves were being phased out, some
> enterprising folk actually made valve replacements circuits using
> semiconductors on a valve base!
>
manufacturers for many years and widely used in professional and industrial
equipment.
> As I recall, one flashover and they were history.
>
Only if they had been incompetently designed.
David.
Brian Gaff
small items run cool.
I have some old 405line projection tubes somewhere. Never run one outside
the light box with its 1inch thick lead glass concave mirror or you will
get an Xray overdose!
Brian
--
Brian Gaff - bri...@blueyonder.co.uk
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in the display name may be lost.
Blind user, so no pictures please!
"Bob Eld" <nsmon...@yahoo.com> wrote in message
news:hg5s0v$530$1...@news.eternal-september.org...
David Looser
> Its purely because of mass production of course. once the main factories
> making valves got below a certain number prices started going up, and vice
> versa for semiconductors of course.
Not "purely". Until the planar technique came along transistor production
was quite labour-intensive. And the Bell Labs patent also helped to keep
transistor prices high whilst it lasted.
David.
Brian Gaff
refering to a whole seven transistors!
I built one of these, but the output transistors were faulty and after ten
minutes they would get very hot and the output would stop. Tuurn it off for
a few minutes and it did it all again. In the end the company sent us a set
of matched GET 114s and all was well!
Brian
--
Brian Gaff - bri...@blueyonder.co.uk
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Engineer" <junk...@rogers.com> wrote in message
news:c2017da0-68b5-47d6...@b15g2000yqd.googlegroups.com...
Brian Gaff
started putting their transistors in opaque bodies and made the transparent
ones with a higher price tag!
They were so crude they did not often know which ones they were making,
having to test them and put them into the bin for the ones they resembled
most.
I once had a set of OC71s that had such a low capacitance they would amplify
at medium wave. My first radio microphone!
Brian
--
Brian Gaff - bri...@blueyonder.co.uk
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"Don Pearce" <sp...@spam.com> wrote in message
news:4b2e74a9....@news.eternal-september.org...
Brian Gaff
Dusty eht units in damp rooms...
Brian
--
Brian Gaff - bri...@blueyonder.co.uk
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"David Looser" <david....@btinternet.com> wrote in message
news:7oniudF...@mid.individual.net...
David Looser
news:rCwVm.15248$Ym4....@text.news.virginmedia.com...
> I have some old 405line projection tubes somewhere. Never run one outside
> the light box with its 1inch thick lead glass concave mirror or you will
> get an Xray overdose!
You mean the Mullard MW6-2?
Not specific to 405-lines of course, it was widely used on the continent in
625-line and even some French 819-line sets.
It ran with 25kV on the final anode, same as a modern colour tube, but
without the lead glass of the colour tube.
David.
Don Pearce
<bri...@blueyonder.co.uk> wrote:
>Who recalls the RT and VC kit transistor radio called the Elegant 7,
>refering to a whole seven transistors!
>I built one of these, but the output transistors were faulty and after ten
>minutes they would get very hot and the output would stop. Tuurn it off for
>a few minutes and it did it all again. In the end the company sent us a set
>of matched GET 114s and all was well!
>
>Brian
Sorry you can't see this, but here's the original ad for the Elegant
Seven at four guineas. Also on this page is my first ever valve amp an
SET (tetrode not triode) down on the right - 3 to 4 watts, it says. It
even worked.
http://www.soundthoughts.co.uk/look/seven.jpg
d
Ian Bell
Yes, integrated circuits went through a similar curve. I have an article
form the 80s I think that bemoans the price of the NE5532 at the time.
Cheers
ian
Ian Bell
And then a few years later they filled them with some opaque goop so you
couldn't and sold clear ones as the OCP71 at a much higher price - bastards!
Cheers
ian
Woody
> Its purely because of mass production of course. once the main
> factories making valves got below a certain number prices
> started going up, and vice versa for semiconductors of course.
> I think one has to be careful if buying the Chinese copies of
> valves around at the current time, as quality control is almost
> non existent, though some Russian ones are made a lot better
> I'm told.
>
> Brian
Not just then, try now! The only source for most valves for audio
amps is Chinese with some Russian hanging around in the
background. The Chinese ones are something over �25 a pop for
KT66 or KT88, but I saw some Russian ones a few months back that
went on eBay ( think it was) for the thick end of a ton apiece.
--
Woody
harrogate three at ntlworld dot com
Keith G
"Brian Gaff" <bri...@blueyonder.co.uk> wrote in message
news:oswVm.15245$Ym4....@text.news.virginmedia.com...
> making valves got below a certain number prices started going up, and vice
> versa for semiconductors of course.
> I think one has to be careful if buying the Chinese copies of valves
> around at the current time, as quality control is almost non existent,
> though some Russian ones are made a lot better I'm told.
Well, I must have been leading a *charmed life* all these years and didn't
know it!!
First, I have never had anything like the 'normal failure rate' in vinyl
that others appear to have experienced and, to top that, I have never had
any problems with a variety of Chinese valves that have passed through my
hands - that's no problems whatsoever, AFAICR...??
CF2 miniature pentode/triode input valves were indistinguishable from
Mullard EC82 (?) replacements; Shuguan EL34 and various Chinese 300B output
valves all worked and sounded perfectly fine - including Golden Dragons
branded 'Audio Note' and 'Chelmer'!
Pity I can't have the same luck with lottery tickets!
@:-)
(In fact, I'd go as far as to say that all my valve and rectifier failures
have beeen Russian and whatever JJ Tesla is!!??)
Keith G
"Keith G" <k...@moirac.adsl24.co.uk>
> CF2 miniature pentode/triode input valves were indistinguishable from
> Mullard EC82 (?) replacements; Shuguan EL34 and various Chinese 300B
> output valves all worked and sounded perfectly fine - including Golden
> Dragons branded 'Audio Note' and 'Chelmer'!
Streuth, that reminds me it's Christmas time again - here's a pic of my
miniatures off on their Christmas Holidays a few years ago!
http://www.moirac.adsl24.co.uk/showntell/Holidays.jpg
And I'm wondering now if I didn't have a Chinese rectifier valve go pop on
me....??
Peter Wieck
> And I'm wondering now if I didn't have a Chinese rectifier valve go pop on
> me....??
Going *POP* on you is the least of your worries. It is when they melt
into a puddle with the subsequent down-line damage.
I do not stray far from Chinese 5AR4s - and I do keep two for bench
testing purposes.
Peter Wieck
Melrose Park, PA
Ian Bell
When you say 'bench testing' do you men testing the bench against molten
glass?
Cheers
ian
Peter Wieck
> When you say 'bench testing' do you men testing the bench against molten
> glass?
Haven't reached that much heat yet - These tubes tend to slag inside
when they fail.
I was given two Chinese 5AR4s as throw-ins with an amp I purchased -
so I keep them for testing 5AR4-based equipment. Right where I can
keep an eye on them and I do not put any good tubes at risk. I am
slowly moving over to SS 5AR4s. The cost for a good slow-start-
mimicking SS 5AR4 is about what I can pay for a NIB/NOS US-made glass
unit so far ($25 or so), but the insane prices I am seeing on eBay has
me re-thinking putting glass units in equipment that has no particular
need for authenticity. And the dozen or so such units I have in my
stock may make a nice retirement nest egg.
Dave Plowman (News)
> http://www.soundthoughts.co.uk/look/valves.jpg
Prices of transistors were dropping rapidly even then. I paid 7/6 for a
red spot (OC71 reject) in '59.
--
*Reality? Is that where the pizza delivery guy comes from?
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
Serge Auckland
envelope leaving the semiconductor exposed, then clean off the gloop with
meths. You then put back the now clean and scraped off cover, and wrapped a
bit of sticky tape round the join. Voila, at least ten bob saved, albeit at
the cost of three hours work!
Oh how we laughed....
S.
Ian Iveson
> I think one has to be careful if buying the Chinese
> copies of valves around at the current time, as quality
> control is almost non existent, though some Russian ones
> are made a lot better I'm told.
Chinese valves haven't all been bad, although most made in
large quantities have been.
I notice Watford Valves, possibly the biggest UK retailer,
refused to sell Chinese valves on grounds of quality up
until recently. Now they offer quite a few.
If anyone's got their finger on the pulse, I wonder how well
Chinese valves are respected these days?
Ian
Phil Allison
"Brian Gaff"
>
> I think one has to be careful if buying the Chinese copies of valves
> around at the current time, as quality control is almost non existent,
> though some Russian ones are made a lot better I'm told.
>
** Why refer to them as " Chinese copies of valves " ??
My info is that the Chinese purchased valve making equipment ( including
dies and materials) from Europe when factories there closed in the 1980s and
transported it to China.
This is so they could easily start making popular audio valves like EL34s,
6L6s and 12AX7s - for which there were no equivalent Chinese types in
production at the time.
.... Phil
Ian Jackson
<sp...@spam.com> writes
the mains power supply so it would also trickle-charge the 9V
(non-rechargeable) battery (which works - provided you start with a new
battery, don't let it discharge too much, and don't over-do the charging
current). I remember it being not the most sensitive of radios, and
unusually noisy. [I think that some the cheap multi-layer capacitors of
the time were bad for that.] Must dig it out, see if it still works, and
maybe fix the 43 year-old noise problem.
--
Ian
Brian Gaff
had a lot of use over the years and the same valves are still in it. So they
do last.
Brian
--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email: bri...@blueyonder.co.uk
______________________________________________________________________________________________________________
"Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
news:50c9bfc...@davenoise.co.uk...
Patrick Turner
> Interesting insight into the way things were in the 60s - I've just
> been reading a Wireless World from November of that year. Valves
> (tubes for those across the pond) were extremely cheap. And
> transistors cost pretty much the same, which is why we treated them
> with kid gloves and thermal shunts when soldering them into circuits.
>
> http://www.soundthoughts.co.uk/look/valves.jpg
>
> Money conversion for the young and foreign:
>
> 20 shillings to the pound, 12 pence to the shilling. A price given as
> 5/6 meant five shillings and six pence. So an ECC84 at 6/6 is 32.5
> pence in today's money. A 28012 transistor, by contrast at 140/- is
> seven pounds - getting on for half the weekly wage of some people back
> then.
>
> I may post some ads for complete equipment later, just to make you
> cry.
>
A KT88 was 23 shillings on that price sheet in 1966.
In Oz, I don't know how much more the price was, but probably a lot.
There were no cheap online credit card sales.
I Googled up inflation since 1966 to 2008 :-
"A basket of goods and services valued at $2.3 in year 1966 , would
in year cost $24.4 in 2008,
average annual inflation rate of 5.8 per cent"
Wage average in Oz in 1966 was about $42 per week. ( over 20 pounds )
If a KT88 was say $4.20, then that'd be 1/10 of AWE. If AWE now is
$1,000 a week, then todays KT88 should be $100.
But it is usually a lot cheaper unless you buy a KT88 that has not
been used much since 1966.
An EL34 was listed at 4/3, or four shillings and threepence, mabye 8/6
in Oz or about 85cents. That was nowhere near half a week's pay, but
everyone who ever bought a new EL34 whinged long and hard about the
price, and many people would *not* replace their tubes - they just let
the amp blow up, put it in the bin, then they went to the store in
1970 and bought a nice new cool running solid state radiogram with the
extra channel and the built in AM radio.
I was a second year carpenter's apprentice in 1966, and every fucken
thing was bleeedin expensive because my wages were maybe $12 a week. I
still lived at home, and could only afford to run a 250cc BSA XC10L, a
1947 side valve POS which had cost me 10 pounds or $20 the year
before. I spent far too much on crummy british motorcycles until my
wages went up and there was lot's of overtime and then in 1972 I could
buy a nearly new 750cc BMW R/75 for $1,650. I still had another $1,700
in the bank I'd saved.
After 1972, hardly anyone I ever met had anything with vacuum tubes in
it.
I probably mixed in the wrong class of people.
Patrick Turner.
Don Pearce
I suspect there will be bigger problems today with the amount of
electronic garbage flying round in the air, but it would be
interesting to see how it holds up. I think I would be going for the
transistors before the caps in a noise search though.
d
Don Pearce
<da...@davenoise.co.uk> wrote:
>In article <4b273468....@news.eternal-september.org>,
> Don Pearce <sp...@spam.com> wrote:
>> Interesting insight into the way things were in the 60s - I've just
>> been reading a Wireless World from November of that year. Valves
>> (tubes for those across the pond) were extremely cheap. And
>> transistors cost pretty much the same, which is why we treated them
>> with kid gloves and thermal shunts when soldering them into circuits.
>
>> http://www.soundthoughts.co.uk/look/valves.jpg
>
>> Money conversion for the young and foreign:
>
>> 20 shillings to the pound, 12 pence to the shilling. A price given as
>> 5/6 meant five shillings and six pence. So an ECC84 at 6/6 is 32.5
>> pence in today's money. A 28012 transistor, by contrast at 140/- is
>> seven pounds - getting on for half the weekly wage of some people back
>> then.
>
>> I may post some ads for complete equipment later, just to make you
>> cry.
>
>Prices of transistors were dropping rapidly even then. I paid 7/6 for a
>red spot (OC71 reject) in '59.
That was cheap, I remember paying something around thirty shillings
for a working one. Sinclair used to buy bags of rejects for nearly
nothing, go through them with a meter to find any that had even a tiny
amount of residual gain then sell them.
d
Ian Jackson
<sp...@spam.com> writes
>
>Sinclair used to buy bags of rejects for nearly
>nothing, go through them with a meter to find any that had even a tiny
>amount of residual gain then sell them.
>
Well, I suppose that's one way of getting a knighthood, and then
elevation to the peerage!
--
Ian
Ian Bell
> In article <4b273468....@news.eternal-september.org>,
> Don Pearce <sp...@spam.com> wrote:
>> Interesting insight into the way things were in the 60s - I've just
>> been reading a Wireless World from November of that year. Valves
>> (tubes for those across the pond) were extremely cheap. And
>> transistors cost pretty much the same, which is why we treated them
>> with kid gloves and thermal shunts when soldering them into circuits.
>
>> http://www.soundthoughts.co.uk/look/valves.jpg
>
>> Money conversion for the young and foreign:
>
>> 20 shillings to the pound, 12 pence to the shilling. A price given as
>> 5/6 meant five shillings and six pence. So an ECC84 at 6/6 is 32.5
>> pence in today's money. A 28012 transistor, by contrast at 140/- is
>> seven pounds - getting on for half the weekly wage of some people back
>> then.
>
>> I may post some ads for complete equipment later, just to make you
>> cry.
>
> Prices of transistors were dropping rapidly even then. I paid 7/6 for a
> red spot (OC71 reject) in '59.
>
I had some of those too. There were also green spot rf ones. I still
have a red spot one. Must be worth a fortune now ;-)
Cheers
Ian
Dave Plowman (News)
Ian Jackson <ianREMOVET...@g3ohx.demon.co.uk> wrote:
> I made an Elegant 7 for my mother-in-law. I still have it. I modified
> the mains power supply so it would also trickle-charge the 9V
> (non-rechargeable) battery (which works - provided you start with a new
> battery, don't let it discharge too much, and don't over-do the charging
> current). I remember it being not the most sensitive of radios, and
> unusually noisy. [I think that some the cheap multi-layer capacitors of
> the time were bad for that.] Must dig it out, see if it still works, and
> maybe fix the 43 year-old noise problem.
I have a 'Good Companion' built using my first week's wages in 1962. Still
works as well as ever - ie not that sensitive. Micro alloy transistors and
transfilters. The ad men were alive and well even then...
--
*TEAMWORK...means never having to take all the blame yourself *
David Looser
>
> I had some of those too. There were also green spot rf ones. I still have
> a red spot one. Must be worth a fortune now ;-)
>
If they are worth a fortune I'm sitting on a gold-mine here!
David.
Jim Lesurf
I think I have some old 'Newmarket' (if that was the name) transistors.
Maybe if these kinds of things are now 'historic relics' I should dig some
of them out... :-) IIRC they are still in the corrugated cardboard in the
boxes in which they were bought.
Slainte,
Jim
--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html
Keith G
"Patrick Turner" <in...@turneraudio.com.au> wrote in message
news:9ea2fd30-5287-46b6...@g1g2000pra.googlegroups.com...
Australians, not 'Poms' *whingeing*...??
(Now, why am I so not surprised to hear that? :-)
and many people would *not* replace their tubes - they just let
the amp blow up, put it in the bin, then they went to the store in
1970 and bought a nice new cool running solid state radiogram with the
extra channel and the built in AM radio.
I was a second year carpenter's apprentice in 1966, and every fucken
thing was bleeedin expensive because my wages were maybe $12 a week. I
still lived at home, and could only afford to run a 250cc BSA XC10L, a
1947 side valve POS which had cost me 10 pounds or $20 the year
before. I spent far too much on crummy british motorcycles until my
wages went up and there was lot's of overtime and then in 1972 I could
buy a nearly new 750cc BMW R/75 for $1,650. I still had another $1,700
in the bank I'd saved.
OK, that's all good - now also crosspost to uk.rec.motorcycles and, at a
thousand posts a day last time I looked, this troll should really *fly*...
Ian Jackson
I don't think that there's any reason to suspect that the Elegant 7
won't perform just as well as a 'new' LW/MW portable radio. Apart from
ceramic IF transformers, the design will be essentially identical.
> I think I would be going for the
>transistors before the caps in a noise search though.
>
Yes, the transistors are the obvious suspects, but I remember reading
(long ago) that some dodgy multi-layer ceramic capacitors can produce
noise.
--
Ian
Don Pearce
Yes they made them in big sheets then chopped them up, leaving jagged
bits hanging off the edges. These would make contact with the main
part of the cap intermittently by arcing, resulting in noise. These
days they all have their edges polished to stop this.
d
Arny Krueger
news:4b273468....@news.eternal-september.org
> Interesting insight into the way things were in the 60s -
> I've just been reading a Wireless World from November of
> that year. Valves (tubes for those across the pond) were
> extremely cheap. And transistors cost pretty much the
> same, which is why we treated them with kid gloves and
> thermal shunts when soldering them into circuits.
>
> http://www.soundthoughts.co.uk/look/valves.jpg
>
> Money conversion for the young and foreign:
>
> 20 shillings to the pound, 12 pence to the shilling. A
> price given as 5/6 meant five shillings and six pence. So
> an ECC84 at 6/6 is 32.5 pence in today's money. A 28012
> transistor, by contrast at 140/- is seven pounds -
> getting on for half the weekly wage of some people back
> then.
>
> I may post some ads for complete equipment later, just to
> make you cry.
I'm betting that Kitty will tell us that he's never had to replace a tube.
;-)
Ian Jackson
<sp...@spam.com> writes
--
Ian
Ian Bell
I also have some 'top hat' types XA???
Cheers
Ian
Ian Bell
That assumes that all that is required to make good tubes is the
equipment. Whether or not the Chinese have the necessary know how as
well is moot.
Cheers
Ian
David Looser
>
> That assumes that all that is required to make good tubes is the
> equipment. Whether or not the Chinese have the necessary know how as well
> is moot.
>
I'm sure that the nation that invented printing, gunpowder and bone china
(amongst many other things) won't have much problem in acquiring the
necessary know-how.
David.
Phil Allison
"Ian Bell= Fucking RATBAG MORON"
>
> Phil Allison wrote:
>> "Brian Gaff"
>>> I think one has to be careful if buying the Chinese copies of valves
>>> around at the current time, as quality control is almost non existent,
>>> though some Russian ones are made a lot better I'm told.
>>>
>>
>>
>> ** Why refer to them as " Chinese copies of valves " ??
>>
>> My info is that the Chinese purchased valve making equipment ( including
>> dies and materials) from Europe when factories there closed in the 1980s
>> and transported it to China.
>>
>> This is so they could easily start making popular audio valves like
>> EL34s, 6L6s and 12AX7s - for which there were no equivalent Chinese
>> types in production at the time.
>>
>>
>
> equipment.
** There is no such assumption within or behind my post
- you fucking ASININE TENTH WIT !!!
..... Phil
Phil Allison
"David Loser"
"Ian Bell Fucking RATBAG "
>>
>> That assumes that all that is required to make good tubes is the
>> equipment. Whether or not the Chinese have the necessary know how as well
>> is moot.
>>
>
> I'm sure
** LOL - Loser is never sure if his ARSE e is on fire or nor !!
> that the nation that invented printing, gunpowder and bone china (amongst
> many other things) won't have much problem in acquiring the necessary
> know-how.
** Shame all the EVIDENCE of the last 20+ years says the exact opposite -
ie Chinese audio valves are still of relatively* poor quality and with very
poor quality control as well.
Virtually all of them come from just one Chinese maker, " Shuguang Electron
Group Co Ltd."
http://www.shuguangelec.com/en/profile.asp
( * relatively = relative to the US, UK and major European brands before
they ceased operations )
..... Phil
Ian Iveson
>>
>> That assumes that all that is required to make good tubes
>> is the equipment. Whether or not the Chinese have the
>> necessary know how as well is moot.
>>
>
> I'm sure that the nation that invented printing, gunpowder
> and bone china (amongst many other things) won't have much
> problem in acquiring the necessary know-how.
Columbus set off with a Chinese map of the world, including
America in its proper location, drawn up before the Chinese
fleet was recalled because of a long period of war. As with
the UK, that fleet was made from pretty much all the trees
they had, which was a lot of trees. Then, as now, they
traded throughout the world without involving themselves in
the politics of distant places, and in the end they all went
home. Gunpowder but no guns, according to my edition of
"Shogun", in which the marauding Mongols arrive with
"thunder bombers", who set fire to bags of powder and hurl
them. Best used downhill against approaching heavy cavalry
so even if the bombers blow themselves up they still
frighten the horses. Guns arrived from Europe, much later.
The Chinese are generally well educated and just as clever
as other humans, so they aren't short of scientific and
engineering knowledge. What they must lack is an adequate
number of experienced technicians who are able to deal with
the everyday variations in industial production processes.
Not just in the assembly but also in the production of the
special materials. The machinery was made in the days when
production managers and technicians needed a real feel for
what they did.
Economically, it seems probable that the plants had become
"cash cows" before they went to China, and have remained so
since. Basically, plants producing products on the down side
of the product life cycle require little invesment and
produce cash until they eventually die. A cash cow is
typically matched with the manufacture of new products on
the rising side of the cycle, which consumes cash because of
continuous growth in turnover. Working for a cash cow is
thoroughly demoralising, especially for engineers. Patrick's
worst nightmare: all bean counting but with absolutely no
beans...extreme make-do-and-mend.
Anyway, for the kind of pace of development in China, plenty
of cash cows are a good alternative to debt, I guess. That's
presumably why they're buying car and aircraft plants for
old models, and countless other examples of outdated but
cheap and functional stuff.
Even if you had all the "know-how" would you, as a
businessman, invest money in producing an improved valve?
Would you replace all those worn machine tools and jigs?
Include the cost of not investing in something sensible.
It's not just the Chinese. *No-one else* was prepared to
invest in those plants. That's why they went to China.
Ian
David Looser
>
> Columbus set off with a Chinese map of the world, including America in its
> proper location, drawn up before the Chinese fleet was recalled because of
> a long period of war. As with the UK, that fleet was made from pretty much
> all the trees they had, which was a lot of trees.
So where does this little bit of bogus "history" come from?
>
> The Chinese are generally well educated and just as clever as other
> humans, so they aren't short of scientific and engineering knowledge.
Exactly.
>
> Economically, it seems probable that the plants had become "cash cows"
> before they went to China, and have remained so since.
Indeed, would valve quality have been any better had the production
equipment stayed in Europe or the US? Both continents make some pretty
shoddy products as well as some superb ones.
David.
Ian Bell
And a Merry Christmas and a Healthy New Year to you too Phil
Cheers
Ian
Andre Jute
The Chinese had a huge headstart in all that knowledge, and having the
machinery; they should have enjoyed all of what is known in economics
as "the advantages of backwardness". If the Chinese were interested in
making good tubes, it would have happened by now. I think we can
assume they're interested in volume well before quantity. No amount of
creepy leftwing excuses can change the outcome: after 20+ years,
Chinese tube quality is *very* patchy.
Andre Jute
Visit Jute on Amps at
http://www.audio-talk.co.uk/fiultra/
"wonderfully well written and reasoned information for the tube audio
constructor"
John Broskie TubeCAD & GlassWare
"an unbelievably comprehensive web site containing vital gems of
wisdom"
Stuart Perry Hi-Fi News & Record Review
David Looser
> The Chinese had a huge headstart in all that knowledge, and having the
> machinery; they should have enjoyed all of what is known in economics
> as "the advantages of backwardness". If the Chinese were interested in
> making good tubes, it would have happened by now. I think we can
> assume they're interested in volume well before quantity. No amount of
> creepy leftwing excuses can change the outcome: after 20+ years,
> Chinese tube quality is *very* patchy.
Which is all beside the point. The Chinese have the know-how, whether they
choose to use it is another matter entirely. If they all come from the same
maker then there is no competitive pressure to improve quality. That's the
way capitalism works, nothing to do with "leftwing excuses".
David.
Ian Iveson
>> Columbus set off with a Chinese map of the world,
>> including America in its proper location, drawn up before
>> the Chinese fleet was recalled because of a long period
>> of war. As with the UK, that fleet was made from pretty
>> much all the trees they had, which was a lot of trees.
>
> So where does this little bit of bogus "history" come
> from?
Since you've already decided it's bogus, why do you want to
know?
I'd be quite interested to know *why* you think it's bogus,
in particular? Pretty much all of history regularly turns
out to be bogus, more or less, in one way or another. The
Chinese were remarkably absent from my school history,
except for some passing mention of Marco Polo, who made
stuff up.
Actually, as with much of my view of history, I can't
remember where the Chinese world map story came from.
Possibly a TV documentary. Of course the details are open to
doubt, but the generality...that Chinese maps of the world
were available before European ones...seems to be generally
accepted. I judge it unlikely that such a huge trading fleet
could have managed to keep its maps secret from the
Europeans.
http://www.chengho.org/news/chinesemap.php
Is what a casual Google came up with. I wonder what's
happened since then?
Makes a nice story anyway. The island of California is an
interesting error. I can see how it might have been made by
explorers arriving from the Pacific, but not by those
arriving by land or along the coast, and yet it appears on
European maps.
>> The Chinese are generally well educated and just as
>> clever as other humans, so they aren't short of
>> scientific and engineering knowledge.
>
> Exactly.
>>
>> Economically, it seems probable that the plants had
>> become "cash cows" before they went to China, and have
>> remained so since.
>
> Indeed, would valve quality have been any better had the
> production equipment stayed in Europe or the US? Both
> continents make some pretty shoddy products as well as
> some superb ones.
Agreed. Of course.
Ian
David Looser
news:F_aWm.131704$jv5.1...@newsfe14.ams2...
> David Looser wrote:
>
>>> Columbus set off with a Chinese map of the world, including America in
>>> its proper location, drawn up before the Chinese fleet was recalled
>>> because of a long period of war. As with the UK, that fleet was made
>>> from pretty much all the trees they had, which was a lot of trees.
>>
>> So where does this little bit of bogus "history" come from?
>
> Since you've already decided it's bogus, why do you want to know?
>
> I'd be quite interested to know *why* you think it's bogus, in particular?
OK, "bogus" was too strong. The map is interesting I agree, and I'm
certainly not calling *it* "bogus, though as yet it's authenticity is
unproven. But who says that Columbus had a copy? Of course we now know that
the Vikings briefly colonised North America in the 14th C, though it's very
unlikely that Columbus would have known about that.
I suppose the phrase that really triggered my use of "bogus" was "As with
the UK, that fleet was made from pretty much all the trees they had, which
was a lot of trees". Do you *really* believe that the British fleet, let
alone the Chinese one, represented "pretty much all the trees they had"?
It's well accepted that the Chinese were at one time a major sea-faring and
trading nation and had excellent ship building skills. Later for reasons
that remain obscure they gave up sea-borne trade and turned inward. The
phrase "the Chinese fleet was recalled because of a long period of war"
doesn't line up with anything I've ever read. I've seen it argued that one
reason that the Chinese-built Mongol fleet for the invasion of Japan was
lost so dramatically in a storm (the original Kamikaze, which means "Divine
Wind") was that the Chinese ship builders, who were working under
sufferance, deliberately constructed the ships to be unseaworthy.
David.
Ian Iveson
>>>> Columbus set off with a Chinese map of the world,
>>>> including America in its proper location, drawn up
>>>> before the Chinese fleet was recalled because of a long
>>>> period of war. As with the UK, that fleet was made from
>>>> pretty much all the trees they had, which was a lot of
>>>> trees.
>>>
>>> So where does this little bit of bogus "history" come
>>> from?
>>
>> Since you've already decided it's bogus, why do you want
>> to know?
>>
>> I'd be quite interested to know *why* you think it's
>> bogus, in particular?
>
> OK, "bogus" was too strong. The map is interesting I
> agree, and I'm certainly not calling *it* "bogus, though
> as yet it's authenticity is unproven. But who says that
> Columbus had a copy? Of course we now know that the
> Vikings briefly colonised North America in the 14th C,
> though it's very unlikely that Columbus would have known
> about that.
But nonetheless likely that he had a copy of the Chinese
one. The story went that it was presented to the King of
Spain as some kind of gift or tribute. If the Chinese had
ceased trading, then they would have nothing to lose.
> I suppose the phrase that really triggered my use of
> "bogus" was "As with the UK, that fleet was made from
> pretty much all the trees they had, which was a lot of
> trees". Do you *really* believe that the British fleet,
> let alone the Chinese one, represented "pretty much all
> the trees they had"?
An overstatement big enough to be obvious hyperbole, I
thought. I do think it true that shipbuilding, here and in
China, became increasingly constrained by a shortage of
suitable remaining trees. I guess that only certain kinds
and sizes of tree were suitable though. Their ships were
much bigger, and there were lots of them, so it seems
reasonable to assume that they used proportionately more
trees. Others were used for houses or fuel. Wherever all
that story came from, I suppose I assimilated it because it
fitted with whatever I thought I already knew.
So, as a matter of interest, how many trees are needed to
make a ship, and how many ships were made? How many trees
are there in a square mile of forest?
And where *did* all the trees go?
Wasn't there a long period of civil and local wars around
what is now China? Perhaps involving Korea and other
emerging border states, and areas which are now China but
weren't at the time?
> It's well accepted that the Chinese were at one time a
> major sea-faring and trading nation and had excellent ship
> building skills. Later for reasons that remain obscure
> they gave up sea-borne trade and turned inward. The phrase
> "the Chinese fleet was recalled because of a long period
> of war" doesn't line up with anything I've ever read. I've
> seen it argued that one reason that the Chinese-built
> Mongol fleet for the invasion of Japan was lost so
> dramatically in a storm (the original Kamikaze, which
> means "Divine Wind") was that the Chinese ship builders,
> who were working under sufferance, deliberately
> constructed the ships to be unseaworthy.
Neither sounds likely as an explanation for why so many
ships seemed to disappear from history. For some reason they
stopped trading all over the world. War at home seems a more
likely cause. Ships don't seem to last long at the best of
times, and once the wars were over they couldn't build more
because they ran out of suitable trees and the age of big
wooden ships was over.
Ian
Trevor Wilson
"David Looser" <david....@btinternet.com> wrote in message
news:7oq5tgF...@mid.individual.net...
**I keep a large box, full of Chinese valves, I purchased to service
equipment. They're all buggered and they're all new or very close to new. I
keep them to remind myself NEVER to buy Chinese valves (unless there is
simply no alternative). Russian valves, by comparison, are generally much,
much better. NOS American, German, Australian and British are better still.
Ah, I remember paying AUS$25.00 each for GE-MOV KT88s. Good times. Great
valves. One of my instructors was on the team that developed the KT88.
--
Trevor Wilson
www.rageaudio.com.au
Phil Allison
"Trevor Wilson"
> **I keep a large box, full of Chinese valves, I purchased to service
> equipment. They're all buggered and they're all new or very close to new.
> I keep them to remind myself NEVER to buy Chinese valves (unless there is
> simply no alternative).
** So you have not bought any Chinese made valves in a long time.
> Russian valves, by comparison, are generally much, much better.
** Found that to be true of the power types (ie EL34, EL84, 6L6 & 6550s )
but not so very much in the case of 'X7s and 'T7s.
> NOS American, German, Australian and British are better still.
** How many of these have you bought lately?
The last time I saw any US made Philips/Sylvania 6L6GCs or 6550As
advertised, they were asking well over $100 each and the sky is the limit
for genuine Mullard EL34s.
Collectors items only - not parts for use in real amps any more.
> Ah, I remember paying AUS$25.00 each for GE-MOV KT88s.
** That would have to be about 40 years ago.
Wanker.
.... Phil
mick
> In article <7opb0gF...@mid.individual.net>, David Looser
> <david....@btinternet.com> wrote:
>> "Ian Bell" <ruffr...@yahoo.com> wrote >
>> >
>> > I had some of those too. There were also green spot rf ones. I still
>> > have a red spot one. Must be worth a fortune now ;-)
>> >
>> >
>> If they are worth a fortune I'm sitting on a gold-mine here!
>
> I think I have some old 'Newmarket' (if that was the name) transistors.
> Maybe if these kinds of things are now 'historic relics' I should dig
> some of them out... :-) IIRC they are still in the corrugated
> cardboard in the boxes in which they were bought.
>
Would those be the ones in the flat cans with yellow & green spots for
audio and a red spot for RF, Jim?
Interesting page for flat cans:
http://homepages.nildram.co.uk/~wylie/NKT/newmarket.htm
Another for "top hat" cans:
http://homepages.nildram.co.uk/~wylie/Ediswan/Ediswan.htm
--
Mick (Working in a M$-free zone!)
Web: http://www.nascom.info
Filtering everything posted from googlegroups to kill spam.
Ian Bell
> On Tue, 15 Dec 2009 12:18:39 +0000, Jim Lesurf wrote:
>
>> In article <7opb0gF...@mid.individual.net>, David Looser
>> <david....@btinternet.com> wrote:
>>> "Ian Bell" <ruffr...@yahoo.com> wrote >
>>>> I had some of those too. There were also green spot rf ones. I still
>>>> have a red spot one. Must be worth a fortune now ;-)
>>>>
>>>>
>>> If they are worth a fortune I'm sitting on a gold-mine here!
>> I think I have some old 'Newmarket' (if that was the name) transistors.
>> Maybe if these kinds of things are now 'historic relics' I should dig
>> some of them out... :-) IIRC they are still in the corrugated
>> cardboard in the boxes in which they were bought.
>>
>
>
> Would those be the ones in the flat cans with yellow & green spots for
> audio and a red spot for RF, Jim?
>
> Interesting page for flat cans:
> http://homepages.nildram.co.uk/~wylie/NKT/newmarket.htm
>
> Another for "top hat" cans:
> http://homepages.nildram.co.uk/~wylie/Ediswan/Ediswan.htm
>
Those are the ones i have - XA101 and XA102. Ediswan, now there's a name
to conjure with.
Cheers
iaN
Dave Plowman (News)
mick <not....@invalid.invalid> wrote:
> Would those be the ones in the flat cans with yellow & green spots for
> audio and a red spot for RF, Jim?
IIRC, it was white spot for RF, green/yellow for IF and red for audio.
--
*Why are a wise man and a wise guy opposites? *
David Looser
> David Looser wrote:
>
>>
>> OK, "bogus" was too strong. The map is interesting I agree, and I'm
>> certainly not calling *it* "bogus, though as yet it's authenticity is
>> unproven. But who says that Columbus had a copy? Of course we now know
>> that the Vikings briefly colonised North America in the 14th C, though
>> it's very unlikely that Columbus would have known about that.
>
> But nonetheless likely that he had a copy of the Chinese one.
Extremely *unlikely* I'd have thought. The general view in Europe at the
time was that if you sailed west across the Atlantic long enough you'd reach
Asia, and there is no evidence that I know of that Columbus knew different.
The object of the exercise was to create a direct link with the spice
islands, bypassing the Arab monopoly on the overland route. And why did
Columbus call the Caribbean the "West Indies" if he knew there was another
continent and another major ocean between there and India?
> The story went that it was presented to the King of Spain as some kind of
> gift or tribute.
There are many stories, not all are true. ;-)
> If the Chinese had
> ceased trading, then they would have nothing to lose.
>
>. I do think
> it true that shipbuilding, here and in China, became increasingly
> constrained by a shortage of suitable remaining trees. I guess that only
> certain kinds and sizes of tree were suitable though.
I'm not sure that's true. It was certainly the case here that the Government
managed several forests specifically to provide timber for ships for the
Royal Navy.
> Their ships were
> much bigger, and there were lots of them, so it seems reasonable to assume
> that they used proportionately more trees.
But then China is a lot bigger than the UK!
>
> And where *did* all the trees go?
>
In the UK mostly as firewood or simply cleared to make way for agriculture.
> Wasn't there a long period of civil and local wars around what is now
> China? Perhaps involving Korea and other emerging border states, and areas
> which are now China but weren't at the time?
Was there?
>
>
> Neither sounds likely as an explanation for why so many ships seemed to
> disappear from history. For some reason they stopped trading all over the
> world. War at home seems a more likely cause. Ships don't seem to last
> long at the best of times, and once the wars were over they couldn't build
> more because they ran out of suitable trees and the age of big wooden
> ships was over.
>
The story I heard (from a TV documentary about Zheng He) was that China
became more inward looking at that time and adopted an isolationist policy
towards the outside world. There was no suggestion that it was anything to
do with either wars or a lack of trees.
David.
Don Pearce
<david....@btinternet.com> wrote:
>> But nonetheless likely that he had a copy of the Chinese one.
>
>Extremely *unlikely* I'd have thought. The general view in Europe at the
>time was that if you sailed west across the Atlantic long enough you'd reach
>Asia, and there is no evidence that I know of that Columbus knew different.
>The object of the exercise was to create a direct link with the spice
>islands, bypassing the Arab monopoly on the overland route. And why did
>Columbus call the Caribbean the "West Indies" if he knew there was another
>continent and another major ocean between there and India?
Columbus was essentially clueless. He knew nothing about America and
never went there until long after it was discovered by John Cabot
(1497). Even then it was South America he visited, not North America.
All he managed to do was wander around the outer reaches of the
Caribbean for a while before being forced home.
As for the West Indies business, well if Columbus was a bit better at
Geography, he would have called them the East Indies, because he knew
he needed to go further West to find the real ones.
d
Jim Lesurf
> >
> > I think I have some old 'Newmarket' (if that was the name)
> > transistors. Maybe if these kinds of things are now 'historic relics'
> > I should dig some of them out... :-) IIRC they are still in the
> > corrugated cardboard in the boxes in which they were bought.
> >
> Would those be the ones in the flat cans with yellow & green spots for
> audio and a red spot for RF, Jim?
> Interesting page for flat cans:
> http://homepages.nildram.co.uk/~wylie/NKT/newmarket.htm
> Another for "top hat" cans:
> http://homepages.nildram.co.uk/~wylie/Ediswan/Ediswan.htm
Crumbs! People have webpages for everything! :-)
Afraid that at the moment I'm not sure which types they are. Not looked at
them for ages.
I think they are in metal cylindrical cans with no flange. They are in a
drawer 'at work'. All being well I'll be popping in to work next week
before Xmas to give good wishes and borrow an oscillator. If I remember
I'll have a look and report what they are. They are part of a stock of ye
anciente components that somehow were left over from days or yore. Never
throw anything away.... I still have a PX4 or 25 IIRC that I use to show
undergrads what electronics used to be like in the days before even *I*
were a lad! :-)
Slainte,
Jim
--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html
David Looser
. I still have a PX4 or 25 IIRC that I use to show
> undergrads what electronics used to be like in the days before even *I*
> were a lad! :-)
>
You mean you aren't using it in an SET amplifier? That'd be *real* HiFi that
would!
David.
Jim Lesurf
The one I have is 'gassed' so doesn't work. I did have a number of old
valves, including PX4 and PX25 types. But over a decade ago I
sold/exchanged the ones that were OK rather than have them sitting doing
nowt when there were clearly people who wanted to use them. Just kept a few
examples for 'educational examples' or as spares for a few valve items I
have.
That said, I did have one of my summer project students once develop a
single-ended transistor amp that used an output transformer, just to play
with. So 'SET' I guess, if T = Transistor. ;->
mick
> In article <00929d5b$0$10724$c3e...@news.astraweb.com>,
> mick <not....@invalid.invalid> wrote:
>> Would those be the ones in the flat cans with yellow & green spots for
>> audio and a red spot for RF, Jim?
>
> IIRC, it was white spot for RF, green/yellow for IF and red for audio.
Quite possible, Dave. I've not had anything to do with those thingies for
many years! I remember that the black glass transistors were red spot for
AF and white spot for RF. Dunno about the flat cans though. I did have a
couple for a while though (and might still have somewhere!)
David Looser
> That said, I did have one of my summer project students once develop a
> single-ended transistor amp that used an output transformer, just to play
> with. So 'SET' I guess, if T = Transistor. ;->
>
As used in car radios at one time. Hybid and early all-transistor car radios
mostly seemed to use a Class-A single-ended power transistor (OC16 or
similar) output stage rather than a Class-B push-pull pair. I guess it was
cheaper and the much higher power consumption of Class-A didn't matter much
in a car.
David.
Don Pearce
Ah, those old Motorola medium and long wave beasts. I remember them
well, with their five mechanical push button tuners.
d
Jim Lesurf
I guess designers of commercial audio amps back then were more habituated
to using transformers than nowdays. I didn't know about the above, but
recall that some early domestic transistor amps included things like
coupling transformers.
BTW Not sure if I'll be able to look at the Newmarket devices tomorrow. May
be delayed by snow! :-)
Don Pearce
<no...@audiomisc.co.uk> wrote:
>I guess designers of commercial audio amps back then were more habituated
>to using transformers than nowdays. I didn't know about the above, but
>recall that some early domestic transistor amps included things like
>coupling transformers.
How about a current guitar practice amplifier?
http://www.soundthoughts.co.uk/look/pignose.jpg
The idea is to sound like a proper valve guitar amplifier, and it sort
of does it.
d
Arny Krueger
Probably driven by the then-current high price of power transistors.
If memory serves, there was a period of time where most of the car radio was
built from tubes that used +12 volts for the B+, and a single power
transistor in the output stage. This eliminated the need for a vibrator and
power transformer to create more typical B+ voltages.
Phil Allison
"Jim Lesurf"
>
> I guess designers of commercial audio amps back then were more habituated
> to using transformers than nowdays. I didn't know about the above, but
> recall that some early domestic transistor amps included things like
> coupling transformers.
** The use of coupling transformers disappeared by the early 70s in ( new)
domestic hi- fi amplifiers.
However, one famous British maker of "professional" audio revived the idea
in the early 80s - a massive leap backwards if there ever was one. Hill
Audio Ltd of Kent.
http://www.hill-audio.com/?page_id=4
Hill produced thousands of truly awful DX700 and DX1000 et alia models that
internally consisted simply of a TO220 style audio amp IC ( TDAxxxx )
driving a transformer and thence rows of Motorola MJ15024s - labelled
with their own number. These ugly boat anchors had huge toroidal
transformers, heatsinks that simply didn't and no fan.
The only overload / SOA protection for the MJs were DC rail fuses.
It blew up if ever it got hot, the speaker cable shorted or the driver
tranny wiggled loose on the PCB.
Most primitive power amps I ever saw.
.... Phil
Jim Lesurf
> http://www.soundthoughts.co.uk/look/pignose.jpg
The transformers look quite small. What's the scale of the picture?
I did once do a 'theoretical' design using two bipolars and couple of
transformers to make a SET power amp, just to work out what kind of gain,
etc, you might get. But never built it as it didn't seem worth trying to
get suitable transformers. Maybe the above did it anyway? :-)
David Looser
news:50ccbae...@audiomisc.co.uk...
> In article <4b2e4ab4....@news.eternal-september.org>, Don Pearce
> <sp...@spam.com> wrote:
>> On Sun, 20 Dec 2009 12:22:40 +0000 (GMT), Jim Lesurf
>> <no...@audiomisc.co.uk> wrote:
>
>> >I guess designers of commercial audio amps back then were more
>> >habituated to using transformers than nowdays. I didn't know about the
>> >above, but recall that some early domestic transistor amps included
>> >things like coupling transformers.
>
>> How about a current guitar practice amplifier?
>
>> http://www.soundthoughts.co.uk/look/pignose.jpg
>
>> The idea is to sound like a proper valve guitar amplifier, and it sort
>> of does it.
>
> The transformers look quite small. What's the scale of the picture?
They do, compare with the size of the screw-heads.
>
> I did once do a 'theoretical' design using two bipolars and couple of
> transformers to make a SET power amp, just to work out what kind of gain,
> etc, you might get. But never built it as it didn't seem worth trying to
> get suitable transformers. Maybe the above did it anyway? :-)
>
That looks like a push-pull amp to me. Aren't those a pair of TO220
transistors either side of the larger transformer?
avid.
Dave Plowman (News)
The size of the output transformer looks more suited to 1 watt types.
--
*Can atheists get insurance for acts of God? *
David Looser
news:50cd136...@davenoise.co.uk...
I don't dispute that for a moment, but they *do* look like a pair of TO220
devices! There are no heatsinks so they are probably well under-run.
David.
keithr
> On Tue, 15 Dec 2009 12:18:39 +0000, Jim Lesurf wrote:
>
>> In article <7opb0gF...@mid.individual.net>, David Looser
>> <david....@btinternet.com> wrote:
>>> "Ian Bell" <ruffr...@yahoo.com> wrote >
>>>> I had some of those too. There were also green spot rf ones. I still
>>>> have a red spot one. Must be worth a fortune now ;-)
>>>>
>>>>
>>> If they are worth a fortune I'm sitting on a gold-mine here!
>> I think I have some old 'Newmarket' (if that was the name) transistors.
>> Maybe if these kinds of things are now 'historic relics' I should dig
>> some of them out... :-) IIRC they are still in the corrugated
>> cardboard in the boxes in which they were bought.
>>
>
>
> Would those be the ones in the flat cans with yellow & green spots for
> audio and a red spot for RF, Jim?
>
> Interesting page for flat cans:
> http://homepages.nildram.co.uk/~wylie/NKT/newmarket.htm
>
> Another for "top hat" cans:
> http://homepages.nildram.co.uk/~wylie/Ediswan/Ediswan.htm
>
RRE. I think that I have an STC "Crystal triode" kicking around somewhere,
Arny Krueger
> I guess designers of commercial audio amps back then were
> more habituated to using transformers than nowdays. I
> didn't know about the above, but recall that some early
> domestic transistor amps included things like coupling
> transformers.
Driver transformers were last used in US built hifi amps, probably in the
origional Acoustic Research amplifier and receiver. Probably early 1970s.
It did not appear that they hindered performance all that much. It was a
pretty passable solution for building a SS amp in the days when
complementary transistors were expensive or simply unavailable.
http://www.hifiengine.com/manuals/acoustic-research/receiver.shtml .
Iain Churches
"Don Pearce" <sp...@spam.com> wrote in message
news:4b2e4ab4....@news.eternal-september.org...
The Pignose is brilliant. I have one.
http://www.kolumbus.fi/iain.churches/Pics/Pignose.jpg
A huge sound from a tiny amp:-)
Iain
Don Pearce
<no...@audiomisc.co.uk> wrote:
>In article <4b2e4ab4....@news.eternal-september.org>, Don Pearce
><sp...@spam.com> wrote:
>> On Sun, 20 Dec 2009 12:22:40 +0000 (GMT), Jim Lesurf
>> <no...@audiomisc.co.uk> wrote:
>
>> >I guess designers of commercial audio amps back then were more
>> >habituated to using transformers than nowdays. I didn't know about the
>> >above, but recall that some early domestic transistor amps included
>> >things like coupling transformers.
>
>> How about a current guitar practice amplifier?
>
>> http://www.soundthoughts.co.uk/look/pignose.jpg
>
>> The idea is to sound like a proper valve guitar amplifier, and it sort
>> of does it.
>
>The transformers look quite small. What's the scale of the picture?
>
>I did once do a 'theoretical' design using two bipolars and couple of
>transformers to make a SET power amp, just to work out what kind of gain,
>etc, you might get. But never built it as it didn't seem worth trying to
>get suitable transformers. Maybe the above did it anyway? :-)
>
>Slainte,
>
>Jim
The whole thing is small - the long side is about three inches. This
is a battery powered amplifier that sees a lot of use in studios. It
sounds "big" when recorded.
d
Don Pearce
It isn't the same without the proper pig's nose volume knob.
d
David Looser
>
> My 'mini guitar amp' is a similar idea, except it's real tubes with
> more controls, headphone, and line out for recording.
>
Interesting choice of valve. Apparently it was designed for use in cascode
VHF amplifiers in TV sets. I guess the nearest European equivalent would be
the ECC84. If anyone wants to try building one I've got a box-full of the
PCC84 (same thing but with 7.0V heater).
David.
Keith G
"flipper" <fli...@fish.net> wrote
> My 'mini guitar amp' is a similar idea, except it's real tubes with
> more controls, headphone, and line out for recording.
>
> http://flipperhome.dyndns.org/Gemini%20x2.htm
>
What I lovely little project - almost makes me wish I was still messing
about with that good DIY valvey stuff!!
@:-)
David Looser
>
> I used a number of tricks. Current mirror under the power tubes for
> automatic bias, input FET buffer done as a HV 'tube' emulator, NPN
> follower tone stack buffer, and NPN phase splitter. But the tubes do
> the 'music' work.
>
Are you using the two halves of one of your double triodes as a push-pull
output pair? I have the service manual somewhere for an Ampex 451 tape
recorder (circa 1965). That uses two double triodes in the line amp, the
second (a 12AT7) configured as a push-pull pair. From the photo it looks as
though your output transformer is a line-matching transformer for 70V/100V
line, such a transformer wouldn't have been designed to cope with DC in the
primary. But if you were able to drive it push-pull you'd get DC
cancellation in the core.
David.
Iain Churches
"flipper" <fli...@fish.net> wrote in message
news:cj40j5hbr6bt6rcjb...@4ax.com...
> My 'mini guitar amp' is a similar idea, except it's real tubes with
> more controls, headphone, and line out for recording.
>
> http://flipperhome.dyndns.org/Gemini%20x2.htm
>
Excellent:-)
Pleased to see that there is someone still left on
UKRA who actually builds something, and with valves
too.
Iain
Iain Churches
Rats!. Do you think mine is a worthless Chinese copy?
Its output is tiny but its sound it *huge*
-:)
Don Pearce
<Iai...@kolumbus.fi> wrote:
I'm sure it is real. Those must number among the last properly
hand-made products in the world - no chance of mass production in
Dafen.
d
TonyL
>>>
>>> http://flipperhome.dyndns.org/Gemini%20x2.htm
>>>
>>
>> Excellent:-)
>
> Thank you.
>
>> Pleased to see that there is someone still left on
>> UKRA who actually builds something, and with valves
>> too.
>
> I've already got the tubes for.
>
Hey Flipper,
Would love to see your amp but I've been getting 404s.
Any suggestions ?
TIA
TonyL
TonyL
>
> Sorry about that. It's running on a little webpal that's sitting on
> the edge and I've got a new puppy that loves to smack the thing into
> brain dead. He also likes to pull cables out of the router on that
> segment..
>
> I just moved it to a more stable location so hopefully it'll stay up
> longer.
>
Thanks Flipper, Gotit :-) Nice work !
Any chance of seeing a schematic ?
Don Pearce
>Well, there's some potentially proprietary stuff in there so I don't
>publish that one.
>
>I can talk about it, though.
By publishing you establish your priority, so go ahead.
d