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Michael Black <et472@ncf.ca>: Jun 08 01:00PM -0400

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Jun 09 07:01AM +1000 > Wanna explain that....   > This is about the 3rd time I've heard that expression "bit coins" in the > last month. What the heck does that mean?   **Do you live in a cave? On Mars? Bitcoins have been in the mainstream media for several years.   > that webpage, no one would know what was on it, so what is the point. > And for $100 you can nearly buy a retail version of Windows 10 (I > think). I recall seeing it at Walmart for $129 a year ago.   **A 1GB flash drive is worth, maybe, a Dollar. A 1TB flash drive is worth more than $100.00. Why are you banging on about a flash drive that is usually a giveaway item? I receive them, free, from some of my suppliers who no longer publish parts catalogues on paper.   > both. Everytime I have to use the WIn 10 computers at the local library, > I have to ask WHY? I can do the same things in XP with a lot less bloat, > less CPU power, less hassle, and less much less tracking.   **My Windows 10 laptop boots in less than 30 seconds, is speedy and easy to use. It is MUCH faster than any Win XP machine I've owned. All done without an SSD too.   > been posted on April 1. > Ebay dont seen to care about prices. As long as an item fits their terms > of service, it's listed. (sensible or not).   **I suspect your posts are April 1st ones. A 1GB flash drive. Bah. I sweep them out with the trash. Not worth bending over to pick up.     -- Trevor Wilson www.rageaudio.com.au

oldschool@tubes.com: Jun 09 08:09AM -0400 On Thu, 8 Jun 2017 15:39:57 +1000, Clifford Heath <no.spam@please.net> wrote:   >to exchangeable tokens. "Why would I give you these nice >vegetables for this inscribed chunk of clay, or that paper?"   >That's all cash is, tokens. That's all Bitcoins are, too.   Yea, but cash is controlled by the government, making it safe. Not that the government is always right, but unless the economy collapses, a dollar will always be worth a dollar and can be used anywhere in the US and many other parts of the world.

oldschool@tubes.com: Jun 09 08:45AM -0400 >> hundred. 1GB is worth, maybe, $1.00. Tops.   >I was wondering if the seller messed up, confusing terms so it's actually >a larger capacity drive.   Actually, NO. I have some identical drives and they are 1gb. The reason I was looking at them, is because I want to buy some of them 1gb drives, if they are about $1 or $2 each. The reason is because I made some linux bootable flash drives. I just plug them into the USB and can boot to Linux instead of Windows. I dont generally use Linux, but if Windows wont boot, they are a handy way to retrieve data, and sometimes even fix Windows.   For some reason, I can NOT make these bootable drives on any flash drives larger than 2gb. They just dont work....   >I paid ten for my first couple of 1gig flash drives, I forget when, a >decade or so ago I'd say. And they had dropped in price by then. Now >one can get much greater capacity for the same or less price.   I paid $150 for a USED 10 mb hard drive in 1990. Thats MEGAbyte, not GIGAbyte.   >makeuse of larger capacity memory cards, I don't think computers have >problems with "too large" flash drives.   > Michael   Yep, some older digital cameras wont take cards larger than a specific size. I have an older Canon, and I cant use cards larger than 16gb. Then again, I see no reason to use a larger card. I can get many thousands of photos on a 16gb card. I doubt I take over 1000 photos in a full year, and I dump photos to my computer at least once every 3 months.   Anyhow, in the case of *bootable* flash drives, it appears that computers DO have problems with "too large" flash drives.     BTW, I dont believe they make a 1tb (TERAbyte) flash drive. The largest I have ever seen in the stores and on ebay is 128gb. I do recall hearing they make or are working on a 256gb flash drive. If you want to talk about portable USB hard drives, yea, they go as high as 2tb, maybe higher, but not flash drives.   But if someone knows of a 1tb flash drive, post the URL.....

Cursitor Doom <curd@notformail.com>: Jun 08 05:28PM Hi all,   I tore down a Marconi signal generator today. It's been awaiting my attention for quite a while. Can't recall the model number off hand but it does 10kHz to 5.4Ghz IIRC. I bought it from some chap who told me it had a faulty smoothing cap in the PSU 'cos it was generating signals with ripple on it. He told me he'd been quoted GBP280 ($387 in US dough as of today's date) for a new replacement from Marconi and I bought it on that understanding. Anyway, I tore it down today and located the said capacitor. Here it is:   https://www.flickr.com/photos/128859641@N02/35050368241/in/dateposted- public/   This is the only pic that came out for some reason, but it's got most of the important info on it. You can't quite see, but it has 5 terminals for some reason, but on the board only 2 of them are connected. It's gone seriously low-res internally, BTW, so *does* need replacing.   Questions: what makes this thing so special as to cost so much? Why have the designers used such a huge capacity cap in this low current drain application? If I can source a generic electrolytic of the same spec or better for < 30 quid, why should I not use that instead of the bespoke replacement??

Winfield Hill <hill@rowland.harvard.edu>: Jun 08 10:39AM -0700 Cursitor Doom wrote...   > I tore down a Marconi signal generator today. ... > faulty smoothing cap in the PSU .. GBP280.   I have a 280-pound capacitor, four of them in fact. Well, they must weigh something in that vicinity. They cost $500 each, including pallet shipping.     -- Thanks, - Win

"Gareth Magennis" <soundserviceleeds@outlook.com>: Jun 08 07:15PM +0100 "Cursitor Doom" wrote in message news:ohc1f2$ki$2@dont-email.me...   Hi all,   I tore down a Marconi signal generator today. It's been awaiting my attention for quite a while. Can't recall the model number off hand but it does 10kHz to 5.4Ghz IIRC. I bought it from some chap who told me it had a faulty smoothing cap in the PSU 'cos it was generating signals with ripple on it. He told me he'd been quoted GBP280 ($387 in US dough as of today's date) for a new replacement from Marconi and I bought it on that understanding. Anyway, I tore it down today and located the said capacitor. Here it is:   https://www.flickr.com/photos/128859641@N02/35050368241/in/dateposted- public/   This is the only pic that came out for some reason, but it's got most of the important info on it. You can't quite see, but it has 5 terminals for some reason, but on the board only 2 of them are connected. It's gone seriously low-res internally, BTW, so *does* need replacing.   Questions: what makes this thing so special as to cost so much? Why have the designers used such a huge capacity cap in this low current drain application? If I can source a generic electrolytic of the same spec or better for < 30 quid, why should I not use that instead of the bespoke replacement??         *************************************************************       I've come across these type of 5 terminal capacitor before. 3 pins are just for mounting and are not used in circuit. (Are they not stamped with an "x"?)       Gareth.

dplatt@coop.radagast.org (Dave Platt): Jun 08 12:00PM -0700 In article <ohc1f2$ki$2@dont-email.me>,   >Questions: what makes this thing so special as to cost so much?   At a guess - exact replacement parts might no longer being made, the equipment manufacturer has a small remaining stock, there may be no other source. Some owners of the equipment (e.g. military and some businesses) may have an "exact replacement only" policy for spare parts, to avoid the need to send equipment through a formal requalification process.   So, Marconi can charge that much for a cap, because there are people willing to pay it (rather than scrap the whole piece of equipment).   >Why have the designers used such a huge capacity cap in this low current >drain application?   Might be "because they could". Or, possibly, some of the downstream circuitry might have poor power-supply rejection, and having a truly huge filter cap might be the only way to get ripple-related noise and sidebands down low enough to meet the device's specs. They might also have figured that this part might be prone to degrade over the years (as it apparently has done?) and they installed one of larger- than-initially-required capacity to stave off the effect of this aging and degradation.   >If I can source a generic electrolytic of the same spec or better for < >30 quid, why should I not use that instead of the bespoke replacement??   The extra hold-down terminals might be needed in order for the device to meet its reliability specifications, when installed under conditions of high vibration and possible acceleration shock (e.g. in military installs, on boats or airplanes). Without the additional pins soldered to the board, vibration could result in the cap shaking back and forth, with all of the stress placed on the two solder joints (and the PCB traces) resulting in stress cracking.   A standard modern cap of the same capacity and voltage rating, and equal or better temperature and lifetime specs, is likely to be a good deal lighter than the original. If you can find one which fits the connection terminals, and don't mind the fact that it might break loose if you use the equipment in a bomber that's flying through intense flak explosions for months on end, I suspect it'd work out just as well for you.

Jan Panteltje <pNa0nStpealmtje@yahoo.com>: Jun 08 06:57PM On a sunny day (Thu, 8 Jun 2017 17:28:02 -0000 (UTC)) it happened Cursitor   >Questions: what makes this thing so special as to cost so much? >Why have the designers used such a huge capacity cap in this low current >drain application?   Nothing, it is a crappy old Philips, the contacts to the pins go wrong too. Just replace with some caps with right capacitance / voltage and sintered wires, not that crap.

John Larkin <jjlarkin@highland_snip_technology.com>: Jun 08 12:19PM -0700 On Thu, 8 Jun 2017 17:28:02 -0000 (UTC), Cursitor Doom >drain application? >If I can source a generic electrolytic of the same spec or better for < >30 quid, why should I not use that instead of the bespoke replacement??   Insane ripoff. Good reason to never buy Marconi.   Looks like you ripped out the hole plating on one pin. With luck, it will be one of the passive mounting pins.     --   John Larkin Highland Technology, Inc picosecond timing precision measurement   jlarkin att highlandtechnology dott com http://www.highlandtechnology.com

Ralph Mowery <rmowery28146@earthlink.net>: Jun 08 03:24PM -0400 In article <mejo0e-ija.ln1@coop.radagast.org>, dplatt@coop.radagast.org says... > formal requalification process.   > So, Marconi can charge that much for a cap, because there are people > willing to pay it (rather than scrap the whole piece of equipment).   Sounds like the $ 100,000 diode for the military that could have been replaced by a diode that cost less than one dollar except for the military spec. Seems the military supply depot did not have any. The company that made them did not have any,so they had to make one. Could not make just one, had to do it in a large batch. Probably made 10 to 20 thousand of them.

Cursitor Doom <curd@notformail.com>: Jun 08 08:27PM On Thu, 08 Jun 2017 12:19:54 -0700, John Larkin wrote: > Looks like you ripped out the hole plating on one pin. With luck, it > will be one of the passive mounting pins.   Fortunately it is. :-)

ohger1s@gmail.com: Jun 08 01:39PM -0700 On Thursday, June 8, 2017 at 1:31:39 PM UTC-4, Cursitor Doom wrote:   > If I can source a generic electrolytic of the same spec or better for < > 30 quid, why should I not use that instead of the bespoke replacement??   Many years ago, my Tek 7603 failed to start. I pulled the power supply out and was driven nuts by a simple DC voltage regulator problem in the power supply. A bypass electrolytic capacitor would have been the obvious solution, except this scope used at least a half dozen extra large Mallory built capacitors in parallel, and there's no way they all died together. Adding a bit of external capacitance though brought the voltage right back and the scope to life. Turns out those big caps were dropping out one by one over the years and gave no indication of anything going wrong as they did, until the very last one opened when the supply went out.   Why did I mention all of this? Because I just removed those big Mallorys and stuck in some standard electrolytics of maybe half the total value and taking up about a tenth of the physical area of the originals, and the scope still runs daily with a perfectly clean and stable trace.   In other words, I doubt you'll see any difference by doing what you instinct tells you. That cap may be very low ESR, have special impedance specs or ripple current specs, but I'd be stunned if it makes any real world difference with off the shelf caps. If it were mine, I'd use Panasonic FR series caps.

N_Cook <diverse@tcp.co.uk>: Jun 08 09:46PM +0100 > Many years ago, my Tek 7603 failed to start. I pulled the power supply out and was driven nuts by a simple DC voltage regulator problem in the power supply. A bypass electrolytic capacitor would have been the obvious solution, except this scope used at least a half dozen extra large Mallory built capacitors in parallel, and there's no way they all died together. Adding a bit of external capacitance though brought the voltage right back and the scope to life. Turns out those big caps were dropping out one by one over the years and gave no indication of anything going wrong as they did, until the very last one opened when the supply went out.   > Why did I mention all of this? Because I just removed those big Mallorys and stuck in some standard electrolytics of maybe half the total value and taking up about a tenth of the physical area of the originals, and the scope still runs daily with a perfectly clean and stable trace.   > In other words, I doubt you'll see any difference by doing what you instinct tells you. That cap may be very low ESR, have special impedance specs or ripple current specs, but I'd be stunned if it makes any real world difference with off the shelf caps. If it were mine, I'd use Panasonic FR series caps.   When Tektronix had a base in Guernsey, Channel Islands, thay adopted the following spares procedure. Each year, divide the stock by half, sell off that half at auction, then double the price of what they kept in stock.

rickman <gnuarm@gmail.com>: Jun 08 04:54PM -0400 N_Cook wrote on 6/8/2017 4:46 PM: > following spares procedure. > Each year, divide the stock by half, sell off that half at auction, then > double the price of what they kept in stock.   And this process led to their going out of business sale?   --   Rick C

tabbypurr@gmail.com: Jun 08 04:06PM -0700 On Thursday, 8 June 2017 19:56:29 UTC+1, Dave Platt wrote: > loose if you use the equipment in a bomber that's flying through > intense flak explosions for months on end, I suspect it'd work out > just as well for you.   Marconi Instruments were hot on vibration tests since they're key to reliability in military use. Competitor equipment often failed their tests.   As well as what has been mentioned, a big cap would presumably help ride over an arcing mains connection, giving reliable service where a lesser device would cause malfunction.   As said if you're just using it on a bench you can put whatever cap you like there. It won't be a low ESR type on a 50Hz PSU. If you glue it down it will improve its shock/vibration resilience, but not to match the original marconi & mil specs.     NT

bitrex <bitrex@de.lete.earthlink.net>: Jun 09 08:00AM -0400 On 06/08/2017 01:28 PM, Cursitor Doom wrote:     > Questions: what makes this thing so special as to cost so much? > Why have the designers used such a huge capacity cap in this low current > drain application?   Probably because they got a bunch of large value weird-ass caps cheap and that's what they use in everything. Like a guy who asked me why they used a 1N4002 in this one mass-produced rack effects box when a 1N4001 would've been fine from a ratings perspective and it's cuz "that's what they use in everything"   > If I can source a generic electrolytic of the same spec or better for < > 30 quid, why should I not use that instead of the bespoke replacement??   They're like 5 bucks:   <http://www.mouser.com/ProductDetail/United-Chemi-Con/ESMH160VSN473MR50T/?qs=sGAEpiMZZMtZ1n0r9vR22dBjIkbB%252b54P4MErU9o8dMQ%3d>

bitrex <bitrex@de.lete.earthlink.net>: Jun 09 08:05AM -0400 On 06/08/2017 01:39 PM, Winfield Hill wrote:   > I have a 280-pound capacitor, four of them in fact. > Well, they must weigh something in that vicinity. > They cost $500 each, including pallet shipping.   The physically largest capacitor I ever saw in person was a PIO type rated IIRC for a couple of uF at several kV; it weighed about as much as a bowling ball and was about the same size

Bert Hickman <bert-hickman@comcast.net>: Jun 09 07:46AM -0500 bitrex wrote:   > The physically largest capacitor I ever saw in person was a PIO type > rated IIRC for a couple of uF at several kV; it weighed about as much as > a bowling ball and was about the same size   Our 170 pound energy discharge capacitors, each 70 uF at 12 kVDC: http://capturedlightning.com/photos/Energy_Discharge_Caps/MAXCAP3.JPG

oldschool@tubes.com: Jun 09 08:02AM -0400 On Fri, 9 Jun 2017 08:05:20 -0400, bitrex <bitrex@de.lete.earthlink.net> wrote:     >The physically largest capacitor I ever saw in person was a PIO type >rated IIRC for a couple of uF at several kV; it weighed about as much as >a bowling ball and was about the same size   At 280 lbs, it would take several big men to move the thing. (Or a forklift). Not the kind of thing you can just replace on your work bench, because the bench would probably collapse.

Jan Panteltje <pNa0nStpealmtje@yahoo.com>: Jun 09 01:14PM On a sunny day (Fri, 9 Jun 2017 08:05:20 -0400) it happened bitrex   >The physically largest capacitor I ever saw in person was a PIO type >rated IIRC for a couple of uF at several kV; it weighed about as much as >a bowling ball and was about the same size   In the sixties I worked in a company that made HV transformers and equipment for power stations, railways, etc, now the caps I have seen in the HV test room were alsmost as big as me. Soem of the transformers required a ladder to climb on those. The caps looked a bit like these: http://www.hvbright.com/products/high-voltage-shunt-capacitor/ Dangerous place...

ohger1s@gmail.com: Jun 09 06:44AM -0700 > At 280 lbs, it would take several big men to move the thing. (Or a > forklift). Not the kind of thing you can just replace on your work > bench, because the bench would probably collapse.     You realize the OP was referring to cost (280 pound sterling), not weight. If you're making a joke, the second poster beat you to it.

Jeff Liebermann <jeffl@cruzio.com>: Jun 08 09:55AM -0700 >Phil is always right. No exceptions.   Well, in my experience on Usenet for more years than I care to admit, Phil is far more often correct than mistaken. I vaguely recall one minor item where I caught a mistake, but most other times, he either had the correct answer, or the correct approach to producing an answer. I could only dream that my batting average is as good as his.   I'm on Usenet to learn. If learning requires tolerating some abuse, I'm fully prepared to accept (and deliver) some. It's much like learning any skill that requires dedication and practice (martial arts, musical instruments, auto repair, etc). The good mentors and instructors are generally quite abusive to the typical student telling them they are worthless fumbling fools, incapable of mastering even the basics, and so on. To many, that's sufficient for them to run screaming in horror, or complaining bitterly to others in hope of gathering support. To the few that actually want to learn, such abuse is an incentive to try harder, learn better, practice more, and demonstrate to the mentor or instructor that they are worthy.   Pick your own path to enlightenment and try not to bite the hand that feeds you knowledge.   Drivel: I once bought a Sony CDP101 at a local thrift shop. It didn't work, so I recycled it, not realizing what it was.   Drivel 2.0: The original CD "Red Book" <https://en.wikipedia.org/wiki/Rainbow_Books#Red_Book_.281980.29> was probably written nearby while I was designing marine radios at Intech Inc during the late 1970's. The data converter division was hosting a group of rather secretive Sony engineers, who were probably working on the A/D and D/A converters for the original CDROM. The red books were actually custom printed red ring binders that the company used for catalogs. They were everywhere and no doubt were used by the Sony engineers for their documentation. <http://802.11junk.com/jeffl/crud/red-book.jpg>     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

tabbypurr@gmail.com: Jun 08 03:55PM -0700 On Thursday, 8 June 2017 17:54:58 UTC+1, Jeff Liebermann wrote: > demonstrate to the mentor or instructor that they are worthy.   > Pick your own path to enlightenment and try not to bite the hand that > feeds you knowledge.   Yes he gets things right. He also gets them wrong and makes a real spectacle of himself. The madness comes out. Regularly. I try to learn from everyone, but I wouldn't want to work with him.     NT

avagadro7@gmail.com: Jun 08 01:31PM -0700 the task is RCA leads from the auto receiver allowing removal for remote parking.   I have some cheapos from Amazon n 4 packaged RCA from 14 years ago ....   I'll try your advice n Crutch where hardware is AAA.   The live vinyl spiral wound 14GA? rec-amp lines at 12' are as live vinyl now as 14 years ago. A section runs across the van floor between seats.   Not disappointed

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