Bad Omen?
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From: Sergey Kubushyn on 29 Jul 2010 20:48 Joerg <invalid(a)invalid.invalid> wrote: > Sergey Kubushyn wrote: >> Joerg <invalid(a)invalid.invalid> wrote: >>> Sergey Kubushyn wrote: >>>> krw(a)att.bizzzzzzzzzzzz <krw(a)att.bizzzzzzzzzzzz> wrote: >>>>> On Thu, 29 Jul 2010 01:10:20 GMT, Sergey Kubushyn <ksi(a)koi8.net> wrote: >>>>> >>>>>> Joerg <invalid(a)invalid.invalid> wrote: >>>>>>> Sergey Kubushyn wrote: >>>>>>>> Tim Williams <tmoranwms(a)charter.net> wrote: >>>>>>>>> "Martin Riddle" <martin_rid(a)verizon.net> wrote in message news:i2ntnv$o1h$1(a)news.eternal-september.org... >>>>>>>>>> Maybe they don't like paying 3x the price for those parts? >>>>>>>>> I don't know about that, I've shopped around and it's no worse than a factor of 2, with most of them being on par or better. >>>>>>>> As a matter of fact Mouser is not _THAT_ bad. It is almost on par with >>>>>>>> Arrow/Avnet/etc. Sometimes even cheaper. And in most cases their markup is >>>>>>>> less than 100%. >>>>>>>> >>>>>>>> That is another twin, DigiKey, that has everything marked up to the ears. I >>>>>>>> never understood why people do purchase anything from them... >>>>>>>> >>>>>>> Because they have the only search engine that works. >>>>>> Do they? >>>>> Yes. >>>> Have you ever tried findchips/octopart? >>>> >>> Have you tried the example I gave you this morning? >> >> So what? Findchips shows quite a bunch. > > > A mere fraction of what Digikey offers. > > >> ... And it is beyond my understanding >> why would one search for those... >> > > Maybe because you don't design for mass production :-) > > I need to see the offerings of half a dozen mfgs right at my finger > tips. At Digikey I do, at Findchips I don't. Eh, if I need a million of 0.1uF ceramic capacitors I simply send an email to all my vendors and let them compete... --- ****************************************************************** * KSI(a)home KOI8 Net < > The impossible we do immediately. * * Las Vegas NV, USA < > Miracles require 24-hour notice. * ******************************************************************
From: Joerg on 29 Jul 2010 21:06 Sergey Kubushyn wrote: > Joerg <invalid(a)invalid.invalid> wrote: >> Sergey Kubushyn wrote: >>> Joerg <invalid(a)invalid.invalid> wrote: >>>> Sergey Kubushyn wrote: >>>>> Joerg <invalid(a)invalid.invalid> wrote: >>>>>> Sergey Kubushyn wrote: >>>> [...] >>>>>>> Just one example--I recently tried to buy several thousands of >>>>>>> BC550/60C transistors. The funny thing was Avnet had BC560CTA @ $0.0163 >>>>>>> each but no BC550C at all. I bought 2 ammopacks of 2,000 for $65 from them >>>>>>> (that was all they had in stock.) On the other hand Arrow only had (and >>>>>>> still have) BC550CTA at the same price but no BC560C at all. That was a >>>>>>> couple of days ago. Now Avnet has 32K of BC550CTA in stock. If you were >>>>>>> shopping at Avnet only a week ago you would've said that BC550C are >>>>>>> unobtanium because they do not have them in stock while both findchips and >>>>>>> octopart kept telling Arrow has plenty in stock. >>>>>>> >>>>>> Just what I said all along, should have gone to Digikey, they have >>>>>> oodles of them: >>>>>> >>>>>> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=BC550CGOS-ND >>>>> If you want to pay 3x the price, sure. And 7,055 pcs is not "oodles." And >>>>> even those are just remnants, the other BC550Cxx are non-stocked. And this >>>>> only one will also go non-stocked when they are bought. >>>>> >>>>> And they are exactly at the same point with BC560C. 4,000 left in stock at >>>>> 2x price and a big fat warning they will go non-stocked once that inventory >>>>> is sold. >>>>> >>>> Sergey, let's face it, nearly all thru-hole stuff is going to head for >>>> lalaland. Ok, we were really early adopters over in Europe back then, >>>> but since the start of my industrial career in 1986 I can't remember any >>>> thru-hole board I have designed. And I've designed tons of boards. >>>> >>>> There will always be mfgs for thru-hole, just like Sovtek and Svetlana >>>> do for tubes, but it's going to be boutique-ware. >>> That is what I'm using them for. Not with tubes but for audio. >>> >>> The rumours about their death are grossly exagerrated. Fairchild makes those >>> full steam and they are dirt cheap. Toshiba is back with their 2SK170 and >>> 2SK369 parts that were discontinued long ago. And those parts are TO-92. >>> BTW, Fairchild picked up a lot of Japanese transistors and now there is >>> plenty of 2SA/SB/SC parts in their lineup. >>> >>> Definitely I could replace BC550/BC560 with SOT-23 BC850/BC860 but it >>> doesn't make any sence because rest of the part is all big thruhole ones. >>> Nobody makes SMD polystyrene capacitors, less for high-tolerance ones. There >>> is no replacement for low-noise RN55/60 resistors (at least cheap one) for >>> sub-millivolt audio circuits. I would love to make SMD version but there is >>> no parts for that... >>> >> They won't go totally belly up by the only places I know that do >> thru-hole mass production are all in China now. So some day you may have >> to buy parts from Asia. > > Nah, I don't do mass-production of those. There is no _THAT_ many people who > want to purchase a high-quality (not audiofool HiEnd one with inferior > parameters but enormous price tag) phono corrector :) My program is a couple > of thousands. And it is not just because of low demand but also because of > component availability. I'm using Russian Military Surplus/Spare Parts > Repository polystyrene capacitors, K71-1 with 0.5% tolerance and that is > limited and finite supply. Once they gone they gone forever. > > That product is hand-assembled so I don't care who does mass production :) > >> If your needs are audio check out the BCX70k. Nice low 1/f corner. > > Thanks, but they are not any better than BC850/860. Roughly the same specs. > > BTW, I'd better go purchase a couple of reels of BC850C and BC860C while > they are available (from Mouser :)) before they gone... > > It is not BJTs that are so rare, it is JFETs... I would've been extremely > happy if 2SK369 existed in SOT-23... There is another problem though--I need > matched pairs of those :( Not something that can be done with Pick-and-Place > machine... > > There are Linear systems LSK389 but they are single source and not very > reliable one... One should be out of his mind to design something with such > a Maximese part... > The only dual FETs I am aware of (I mean that are left) are RF transistors. But it's MOSFETs. And even then you often down know how they track because most are multi-chip, meaning just two devices in one package, hoping that they come from the same area on the same wafer. Even then tracking won't be good. > As for the capacitors, Panasonic makes SMD polyphenylensulfide (hope I > spelled it right) ones that are supposedly on par with polypropylens but I > didn't try them yet. And the tolerance issue remains--they are 5%... > I've had that issue with 2x45 degree phase shifters in late 80s when helping another team. Had told them not to use direct conversion but ... Anyhow, we paid through the nose for 0.5% film caps. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Joerg on 29 Jul 2010 21:09 Sergey Kubushyn wrote: > Joerg <invalid(a)invalid.invalid> wrote: >> Sergey Kubushyn wrote: >>> Joerg <invalid(a)invalid.invalid> wrote: >>>> Sergey Kubushyn wrote: >>>>> krw(a)att.bizzzzzzzzzzzz <krw(a)att.bizzzzzzzzzzzz> wrote: >>>>>> On Thu, 29 Jul 2010 01:10:20 GMT, Sergey Kubushyn <ksi(a)koi8.net> wrote: >>>>>> >>>>>>> Joerg <invalid(a)invalid.invalid> wrote: >>>>>>>> Sergey Kubushyn wrote: >>>>>>>>> Tim Williams <tmoranwms(a)charter.net> wrote: >>>>>>>>>> "Martin Riddle" <martin_rid(a)verizon.net> wrote in message news:i2ntnv$o1h$1(a)news.eternal-september.org... >>>>>>>>>>> Maybe they don't like paying 3x the price for those parts? >>>>>>>>>> I don't know about that, I've shopped around and it's no worse than a factor of 2, with most of them being on par or better. >>>>>>>>> As a matter of fact Mouser is not _THAT_ bad. It is almost on par with >>>>>>>>> Arrow/Avnet/etc. Sometimes even cheaper. And in most cases their markup is >>>>>>>>> less than 100%. >>>>>>>>> >>>>>>>>> That is another twin, DigiKey, that has everything marked up to the ears. I >>>>>>>>> never understood why people do purchase anything from them... >>>>>>>>> >>>>>>>> Because they have the only search engine that works. >>>>>>> Do they? >>>>>> Yes. >>>>> Have you ever tried findchips/octopart? >>>>> >>>> Have you tried the example I gave you this morning? >>> So what? Findchips shows quite a bunch. >> >> A mere fraction of what Digikey offers. >> >> >>> ... And it is beyond my understanding >>> why would one search for those... >>> >> Maybe because you don't design for mass production :-) >> >> I need to see the offerings of half a dozen mfgs right at my finger >> tips. At Digikey I do, at Findchips I don't. > > Eh, if I need a million of 0.1uF ceramic capacitors I simply send an email > to all my vendors and let them compete... > On my projects there usually isn't time for that. And this was just an example. It's even worse for specialty stuff such as RF caps that are high voltage. Without Digikey that would take forever. Like it did in the early 90's. On my designs there are typically between 50 and several hundred different discrete parts. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
From: Sergey Kubushyn on 29 Jul 2010 21:43 Joerg <invalid(a)invalid.invalid> wrote: > Sergey Kubushyn wrote: >> Joerg <invalid(a)invalid.invalid> wrote: >>> Sergey Kubushyn wrote: >>>> Joerg <invalid(a)invalid.invalid> wrote: >>>>> Sergey Kubushyn wrote: >>>>>> krw(a)att.bizzzzzzzzzzzz <krw(a)att.bizzzzzzzzzzzz> wrote: >>>>>>> On Thu, 29 Jul 2010 01:10:20 GMT, Sergey Kubushyn <ksi(a)koi8.net> wrote: >>>>>>> >>>>>>>> Joerg <invalid(a)invalid.invalid> wrote: >>>>>>>>> Sergey Kubushyn wrote: >>>>>>>>>> Tim Williams <tmoranwms(a)charter.net> wrote: >>>>>>>>>>> "Martin Riddle" <martin_rid(a)verizon.net> wrote in message news:i2ntnv$o1h$1(a)news.eternal-september.org... >>>>>>>>>>>> Maybe they don't like paying 3x the price for those parts? >>>>>>>>>>> I don't know about that, I've shopped around and it's no worse than a factor of 2, with most of them being on par or better. >>>>>>>>>> As a matter of fact Mouser is not _THAT_ bad. It is almost on par with >>>>>>>>>> Arrow/Avnet/etc. Sometimes even cheaper. And in most cases their markup is >>>>>>>>>> less than 100%. >>>>>>>>>> >>>>>>>>>> That is another twin, DigiKey, that has everything marked up to the ears. I >>>>>>>>>> never understood why people do purchase anything from them... >>>>>>>>>> >>>>>>>>> Because they have the only search engine that works. >>>>>>>> Do they? >>>>>>> Yes. >>>>>> Have you ever tried findchips/octopart? >>>>>> >>>>> Have you tried the example I gave you this morning? >>>> So what? Findchips shows quite a bunch. >>> >>> A mere fraction of what Digikey offers. >>> >>> >>>> ... And it is beyond my understanding >>>> why would one search for those... >>>> >>> Maybe because you don't design for mass production :-) >>> >>> I need to see the offerings of half a dozen mfgs right at my finger >>> tips. At Digikey I do, at Findchips I don't. >> >> Eh, if I need a million of 0.1uF ceramic capacitors I simply send an email >> to all my vendors and let them compete... >> > > On my projects there usually isn't time for that. And this was just an > example. It's even worse for specialty stuff such as RF caps that are > high voltage. Without Digikey that would take forever. Like it did in > the early 90's. > > On my designs there are typically between 50 and several hundred > different discrete parts. I agree there are some reasons why people stay with them. They would've ran out of business if there were none :) But in my case there is nothing that would've justified paying a higher price for the same parts. I do even purchase from them on those rare occasions they have something in stock that nobody else does but that is extremely rare... --- ****************************************************************** * KSI(a)home KOI8 Net < > The impossible we do immediately. * * Las Vegas NV, USA < > Miracles require 24-hour notice. * ******************************************************************
From: Joerg on 29 Jul 2010 21:45
Sergey Kubushyn wrote: > Joerg <invalid(a)invalid.invalid> wrote: >> Sergey Kubushyn wrote: >>> Joerg <invalid(a)invalid.invalid> wrote: >>>> Sergey Kubushyn wrote: >>>>> Joerg <invalid(a)invalid.invalid> wrote: >>>>>> Sergey Kubushyn wrote: >>>>>>> krw(a)att.bizzzzzzzzzzzz <krw(a)att.bizzzzzzzzzzzz> wrote: >>>>>>>> On Thu, 29 Jul 2010 01:10:20 GMT, Sergey Kubushyn <ksi(a)koi8.net> wrote: >>>>>>>> >>>>>>>>> Joerg <invalid(a)invalid.invalid> wrote: >>>>>>>>>> Sergey Kubushyn wrote: >>>>>>>>>>> Tim Williams <tmoranwms(a)charter.net> wrote: >>>>>>>>>>>> "Martin Riddle" <martin_rid(a)verizon.net> wrote in message news:i2ntnv$o1h$1(a)news.eternal-september.org... >>>>>>>>>>>>> Maybe they don't like paying 3x the price for those parts? >>>>>>>>>>>> I don't know about that, I've shopped around and it's no worse than a factor of 2, with most of them being on par or better. >>>>>>>>>>> As a matter of fact Mouser is not _THAT_ bad. It is almost on par with >>>>>>>>>>> Arrow/Avnet/etc. Sometimes even cheaper. And in most cases their markup is >>>>>>>>>>> less than 100%. >>>>>>>>>>> >>>>>>>>>>> That is another twin, DigiKey, that has everything marked up to the ears. I >>>>>>>>>>> never understood why people do purchase anything from them... >>>>>>>>>>> >>>>>>>>>> Because they have the only search engine that works. >>>>>>>>> Do they? >>>>>>>> Yes. >>>>>>> Have you ever tried findchips/octopart? >>>>>>> >>>>>> Have you tried the example I gave you this morning? >>>>> So what? Findchips shows quite a bunch. >>>> A mere fraction of what Digikey offers. >>>> >>>> >>>>> ... And it is beyond my understanding >>>>> why would one search for those... >>>>> >>>> Maybe because you don't design for mass production :-) >>>> >>>> I need to see the offerings of half a dozen mfgs right at my finger >>>> tips. At Digikey I do, at Findchips I don't. >>> Eh, if I need a million of 0.1uF ceramic capacitors I simply send an email >>> to all my vendors and let them compete... >>> >> On my projects there usually isn't time for that. And this was just an >> example. It's even worse for specialty stuff such as RF caps that are >> high voltage. Without Digikey that would take forever. Like it did in >> the early 90's. >> >> On my designs there are typically between 50 and several hundred >> different discrete parts. > > I agree there are some reasons why people stay with them. They would've ran > out of business if there were none :) > > But in my case there is nothing that would've justified paying a higher > price for the same parts. I do even purchase from them on those rare > occasions they have something in stock that nobody else does but that is > extremely rare... > I and my clients only purchase prototype quantities there. IME they are mostly too expensive for larger production runs. On prototypes, however, only time matters. Cost really doesn't. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM. |