This site looks great and reasonably priced.. but doesn't seem accommodating to US voltages... :/
The only decent site I've been able to find is Antek - AN-4225
but even these are a little pricey... any other good sites?
Gold Prices may or may not be in a bubble,( there is some bubble ) the higher prices we are paying for everything is not just due to demand , its due to the loss of value in the dollar.
as long as Oil is tied to the dollar, we will see a continuous rise in prices world wide on everything ..
as long as Oil is tied to the dollar, we will see a continuous rise in prices world wide on everything ..
as long as Oil is tied to the dollar, we will see a continuous rise in prices world wide on everything ..[/QUOTE]
True ! but I don't even want to imagine what will happen here when oil stops being tied to dollar which will stop forcing the whole world to acquire it and will stop america's credit line. It is simply "unimaginable"
True ! but I don't even want to imagine what will happen here when oil stops being tied to dollar which will stop forcing the whole world to acquire it and will stop america's credit line. It is simply "unimaginable"
I picked up a bunch of toroidal Power transformers cheap surplus a few years ago, and turned them around and experimentally found they would work for audio output xformers as long as they weren't overloaded. Some worked (had a high enough impedance), others didn't. But those that did I just put aside. In some ways they had better frequency response than actual output transfomers of equivalent power, but in others (e.g. the lower impedances and inconsistency between instances of the same xformer) they were worse.
Also, I got into noticing that toroids worked great but fell into 'catastrophic' collapses at higher wattages, rather suddenly, while regular xformers deteriorated the signal more gradually.
Also, I got into noticing that toroids worked great but fell into 'catastrophic' collapses at higher wattages, rather suddenly, while regular xformers deteriorated the signal more gradually.
Thanks! That's just the thing.... I've used Airlink in the past when a designer for my then employers but I didn't know they will sell one off quantities
Hmmm.... It would seem that by the time P+P and VAT have been added on it's only a couple of £ cheaper then other sources
It's still a useful resource though.
As one of those countries that doesn't usually have a VAT, I sort of like it. When the VAT is low you know there is a lot of mark-up. When it is high that means to me you are dealing with the folks really doing the work, fewer middle-men!
As to the two sites posted both seem to have reasonable prices knowing the rise in cost of materials. I also expect both manufacturers to have high quality standards.
I do have several transformers around that are not well made. Some are inefficient and heat up too much, others really don't quite meet spec.s and the worst suffer insulation failures. In the safe failure mode that means they blow a fuse and never work again. In the nasty failure mode they either pass the line voltage to the output or catch fire!
But the bottom line is that copper prices may drop a bit, but the pass through prices will be slower to fall. So buying now is reasonable. If prices really fall, then it is also likely that means you won't have any money either!
lucky to 'save' this neat trafo, from an old B&O thing
and a nice heat sink
well, I suppose its a double C-core trafo
one lower volatge, max voltage is rather nice, with 2x 25V
but I don't expect more than 150VA max
I see two bobbins which points in the direction of a single c-core (one bobbin on each leg).
It also might be a UI core (same geometry as c-core but made of stamped laminations instead of the "wound" c-core).
Definitely a (bit rusty) single c-core.
It has a "gap" in the middle (c-core is two equal halves, you see the band holding the halves together).
Normally the halves are pressed tightly together (minimal gap), but high quality transformers can have a real (minor) gap to make the core less prone to saturation (can happen when there is DC like low frequency line pollution).
The single c-core is a good geometry as most of the core is "covered" by the bobbins (minimal strayfields, approaching toroidal core properties in that regard).
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I almost hate to make a suggestion justifying the new norm, but line frequency transformers just aren't getting specified in new designs like in the past except maybe in ultra hi-rel or low noise applications. Since switchers use a small fraction of the wire and no steel, orders for small steel cores and line transformers are probably permanently down, which makes the likelihood of getting in on a good 'volume price' less likely as time goes on..
last i heard the transformer prices were through the roof because china was expanding so rapidly.
but the transformers they are buying are high efficiency types and they use high quality silicon steel.
not the cheap stuff they make E cores out of.
but that does not explain the 4$/lb copper price.
Neither does it explain why, if copper is 7$/kilogram, does copper wire cost $9 per pound!
It does not explain why copper sheet metal is $14 per pound.
Why is 6061-T6 $4/lb? when aluminum is 1$/lb on the futures markets?
steel is well over 1$/lb these days in parts of the country, and if you can find it for less than 50 cents per pound at a scrap yard you're doing good!
but the transformers they are buying are high efficiency types and they use high quality silicon steel.
not the cheap stuff they make E cores out of.
but that does not explain the 4$/lb copper price.
Neither does it explain why, if copper is 7$/kilogram, does copper wire cost $9 per pound!
It does not explain why copper sheet metal is $14 per pound.
Why is 6061-T6 $4/lb? when aluminum is 1$/lb on the futures markets?
steel is well over 1$/lb these days in parts of the country, and if you can find it for less than 50 cents per pound at a scrap yard you're doing good!
Maybe they want to get paid for manufacturing the wire, put it on rolls, packaging, distributing etc. ?
I know, i never worked for free, most people don't, unless it's for charity.
Why not buy a lump of alu, and hammer the plates yourself, even better, stretch your own wire from a big lump of copper, then give it some laquer.
Best regards
Ebbe
I don't know where you get your prices.
In small quantities I pay $.529 a pound for steel. $2.95 a pound for aluminum sheet and $36 a pound for high quality 36 gauge copper wire.
My scrap steel brings in $.12 a pound and aluminum around $.90.
But I really do like selling scrap copper wire at $1.10 a pound!
The price of metals is up, but it was so low for so long... The quality is also up!
Gold is up because people with money are afraid to invest. Typically Govt bonds have been solid and dependable investments, banks are also pretty safe. At present, investors are suspicious of govts ability to repay, and also banks exposures. The outcome is that gold is a safe haven. Some would argue that gold has not risen in price, but the amount of cash being printed in the last four years has just devalued its worth.
Copper has gone up because its price fixed apparently, Ive rad several articles from different sources.
BBC NEWS | Business | Price-fixing raids on mining giants
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