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#1
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2200uF 60V tantalum capacitors
One of the last stumbling blocks in getting simpler power supplies to operate over a wide environmental range, is the capacitors. Using tantalums gets predictable performance. There are not too many places where the application pays - designers tend to work their way around the problem, using other methods. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 RL |
#2
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"legg" wrote in message
... Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 Wow, that's a neat bit of black box... Too bad tantalums are notorious for making messes... Tim -- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @ http://webpages.charter.net/dawill/tmoranwms |
#3
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legg wrote:
One of the last stumbling blocks in getting simpler power supplies to operate over a wide environmental range, is the capacitors. Using tantalums gets predictable performance. There are not too many places where the application pays - designers tend to work their way around the problem, using other methods. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 RL Those must be HEAVY if it costs $40 to ship 'em. )-: mike -- Return address is VALID. Wanted, Slot 1 Motherboard 500MHz Tek DSOscilloscope TDS540 Make Offer http://nm7u.tripod.com/homepage/te.html Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121 Bunch of stuff For Sale and Wanted at the link below. http://www.geocities.com/SiliconValley/Monitor/4710/ |
#4
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mike wrote:
legg wrote: One of the last stumbling blocks in getting simpler power supplies to operate over a wide environmental range, is the capacitors. Using tantalums gets predictable performance. There are not too many places where the application pays - designers tend to work their way around the problem, using other methods. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 RL Those must be HEAVY if it costs $40 to ship 'em. )-: mike I'd say heavy case of fee avoidance. The seller listed the weight at "8.7oz (246grams) each." |
#5
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On Sun, 19 Dec 2004 03:19:28 -0600, "Tim Williams"
wrote: "legg" wrote in message .. . Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 Wow, that's a neat bit of black box... Too bad tantalums are notorious for making messes... I think the 'notorious' problems involved either non-hermetically sealed parts, copper casings, or oversress / reverse stress of solid types. These ain't broke, but obviously could be killed if the user tried hard enough, RL |
#6
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On Sun, 19 Dec 2004 15:35:35 GMT, c a l a n d e
wrote: mike wrote: legg wrote: One of the last stumbling blocks in getting simpler power supplies to operate over a wide environmental range, is the capacitors. Using tantalums gets predictable performance. There are not too many places where the application pays - designers tend to work their way around the problem, using other methods. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 RL Those must be HEAVY if it costs $40 to ship 'em. )-: mike I'd say heavy case of fee avoidance. The seller listed the weight at "8.7oz (246grams) each." Actually, as the seller, I can say it was just a precaution. The price of shipping can get that high for insured priority post to many places. The bidder will be charged for cost of the actual postage fees. I guess this could have been made more explicit. RL |
#7
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legg wrote:
On Sun, 19 Dec 2004 15:35:35 GMT, c a l a n d e wrote: mike wrote: legg wrote: One of the last stumbling blocks in getting simpler power supplies to operate over a wide environmental range, is the capacitors. Using tantalums gets predictable performance. There are not too many places where the application pays - designers tend to work their way around the problem, using other methods. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 RL Those must be HEAVY if it costs $40 to ship 'em. )-: mike I'd say heavy case of fee avoidance. The seller listed the weight at "8.7oz (246grams) each." Actually, as the seller, I can say it was just a precaution. The price of shipping can get that high for insured priority post to many places. The bidder will be charged for cost of the actual postage fees. I guess this could have been made more explicit. RL We can't tell what you meant. I'd expect to be bound by the actual written terms of the auction. There's a general trend toward INFLATED shipping charges on EBAY. I suspect that fee avoidance is a part of it. Some openly admit to padding their profit. Some buyers seem to lose sight of the total cost and just bid the price up anyway, so it works. A shipping charge 3X what might be considered reasonable and 40X the opening bid is a RED flag. Deception in one area is a good indicator of deception in other areas. I have no information either way about this poster; just speaking generally. While I'm on the soapbox... There's also another interesting trend. Outright lying about the product, either by comission or omission. Let the auction end then disclose the problem. Buyers seem to just pay the inflated price anyway. Most of what I've been involved with has to do with missing or broken "accessory items" that are absolutely necessary to get it to work. I get annoyed when I lose the opportunity to buy a junker at a junker price. I long for the good old days when (most) people were less likely to try to sneak one by you. mike -- Return address is VALID. Wanted, Slot 1 Motherboard 500MHz Tek DSOscilloscope TDS540 Make Offer http://nm7u.tripod.com/homepage/te.html Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121 Bunch of stuff For Sale and Wanted at the link below. http://www.geocities.com/SiliconValley/Monitor/4710/ |
#8
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In message , legg
writes One of the last stumbling blocks in getting simpler power supplies to operate over a wide environmental range, is the capacitors. Using tantalums gets predictable performance. There are not too many places where the application pays - designers tend to work their way around the problem, using other methods. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 RL 2200uf Tantalums? Are you serious? -- Chris Morriss |
#9
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On Sun, 19 Dec 2004 11:21:25 -0800, mike wrote:
There's a general trend toward INFLATED shipping charges on EBAY. I suspect that fee avoidance is a part of it. Some openly admit to padding their profit. Some buyers seem to lose sight of the total cost and just bid the price up anyway, so it works. A shipping charge 3X what might be considered reasonable and 40X the opening bid is a RED flag. Deception in one area is a good indicator of deception in other areas. I have no information either way about this poster; just speaking generally. The format provided by e-bay makes it difficult to enter an advert without filling in a 'fixed' shiping cost, if origin is non-US. I suppose there are ways to smooth it out, but I have no experience with the format. My research for insured, registered postal service to Australia gave me a Cdn$80 figure; to UK it was Cdn$50. Obviously a customer would likely choose a slower verion, at reduced expense, if he had some confidence in the supplier and was in no great rush. Shipping to US is likely less, but quoting a low 'fixed' rate could obviously create problems for the supplier. I personally prefer standard surface parcel post, which is quite inexpensive, when purchasing. Strangely, some suppliers won't do it that way. While I'm on the soapbox... There's also another interesting trend. Outright lying about the product, either by comission or omission. Let the auction end then disclose the problem. Buyers seem to just pay the inflated price anyway. Most of what I've been involved with has to do with missing or broken "accessory items" that are absolutely necessary to get it to work. I get annoyed when I lose the opportunity to buy a junker at a junker price. Though I haven't bought through e-bay for some years, I've always been suspicious when bid limits were reached but not exceeded - suggesting that someone had a method to probe your limit and get you to pay it, without exposing themselves to the same risk. It's easier to figure out how a last minute bid can beat you by a piddling amount - just takes a well-synchronized clock. Generally it's too expensive to buy junk this way - but lack of other opportunities, andsome luck can nudge ebay's usefulness upwards, for many. RL |
#10
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On Sun, 19 Dec 2004 20:30:59 +0000, Chris Morriss
wrote: In message , legg writes One of the last stumbling blocks in getting simpler power supplies to operate over a wide environmental range, is the capacitors. Using tantalums gets predictable performance. There are not too many places where the application pays - designers tend to work their way around the problem, using other methods. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 RL 2200uf Tantalums? Are you serious? You bet. RL |
#11
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Behold, legg signalled from keyed 4-1000A filament:
On Sun, 19 Dec 2004 03:19:28 -0600, "Tim Williams" wrote: "legg" wrote in message . .. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 Wow, that's a neat bit of black box... Too bad tantalums are notorious for making messes... I think the 'notorious' problems involved either non-hermetically sealed parts, copper casings, or oversress / reverse stress of solid types. These ain't broke, but obviously could be killed if the user tried hard enough, RL Like: 2,200uF @ 60V? I thought you said 60uF @ 2,200V ;-))))))) -- Gregg t3h g33k "Ratings are for transistors....tubes have guidelines" http://geek.scorpiorising.ca |
#12
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"legg" wrote in message ... One of the last stumbling blocks in getting simpler power supplies to operate over a wide environmental range, is the capacitors. Using tantalums gets predictable performance. There are not too many places where the application pays - designers tend to work their way around the problem, using other methods. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 With outrageously expensive shipping, too - $40.00. No one would want to pay more than a few dollars for those, considering. RL |
#13
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"mike" wrote in message ... [snip] We can't tell what you meant. I'd expect to be bound by the actual written terms of the auction. There's a general trend toward INFLATED shipping charges on EBAY. I suspect that fee avoidance is a part of it. Some openly admit to padding their profit. Some buyers seem to lose sight of the total cost and just bid the price up anyway, so it works. A shipping charge 3X what might be considered reasonable and 40X the opening bid is a RED flag. Deception in one area is a good indicator of deception in other areas. I agree. I've now seen many auctions that do exactly this: start at a dollar with S&H fees of many times the starting fee, just to 'make sure' the seller will not lose money. I have no information either way about this poster; just speaking generally. While I'm on the soapbox... Right. That's why it's often called Sleaze Bay. Here's a very good article on it. http://www.forbes.com/asap/2000/1127/134.html There's also another interesting trend. Outright lying about the product, either by comission or omission. Let the auction end then disclose the problem. Buyers seem to just pay the inflated price anyway. Most of what I've been involved with has to do with missing or broken "accessory items" that are absolutely necessary to get it to work. I get annoyed when I lose the opportunity to buy a junker at a junker price. I long for the good old days when (most) people were less likely to try to sneak one by you. mike |
#14
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In article ,
legg wrote: On Sun, 19 Dec 2004 03:19:28 -0600, "Tim Williams" wrote: "legg" wrote in message .. . Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 Wow, that's a neat bit of black box... Too bad tantalums are notorious for making messes... I think the 'notorious' problems involved either non-hermetically sealed parts, copper casings, or oversress / reverse stress of solid types. These ain't broke, but obviously could be killed if the user tried hard enough, RL Cheap tantalums do have reliability problems. I have worked in failure analysis on military electronics for over 30 years and can tell you that the number of electrically defective tantalums that I have come upon can be counted on the fingers of one hand. And most of those were the ones which used sulfuric acid as the electrolyte. A qualified production line, burn-in and testing will insure trouble free operation for many years. Al |
#15
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On Mon, 20 Dec 2004 14:34:27 GMT, Al wrote:
In article , legg wrote: On Sun, 19 Dec 2004 03:19:28 -0600, "Tim Williams" wrote: "legg" wrote in message .. . Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 Wow, that's a neat bit of black box... Too bad tantalums are notorious for making messes... I think the 'notorious' problems involved either non-hermetically sealed parts, copper casings, or oversress / reverse stress of solid types. These ain't broke, but obviously could be killed if the user tried hard enough, Cheap tantalums do have reliability problems. I have worked in failure analysis on military electronics for over 30 years and can tell you that the number of electrically defective tantalums that I have come upon can be counted on the fingers of one hand. And most of those were the ones which used sulfuric acid as the electrolyte. A qualified production line, burn-in and testing will insure trouble free operation for many years. The switch to silver casings and hermetic glass-to-metal seals addressed the problem with the electrolyte used in wet tantalums. The later use of tantalum casings was apparently a belt-plus-braces solution - the improved part types needed requalification, anyways, so why not....... All the wet ones I've seen fail, used rubber/plastic/epoxy types of seals, or plated copper casings. I inspected the guts of one assembly, in order to get a better idea of what kind of aminal was being dealt with. No sign of corrosion, oxidation, pitting, fatigue or leakage anywhere. It was a pain, but it had to be done before their usefulness could be established to any extent. Testing only tells you so much about a black box. RL |
#16
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On Sun, 19 Dec 2004 06:48:53 GMT, legg wrote:
One of the last stumbling blocks in getting simpler power supplies to operate over a wide environmental range, is the capacitors. Using tantalums gets predictable performance. There are not too many places where the application pays - designers tend to work their way around the problem, using other methods. Others may have other ideas where to stick them. http://cgi.ebay.com/ws/eBayISAPI.dll...tem=3861637697 Well, for whatever the reasons, it seems there are no bidders for such critters. http://makeashorterlink.com/?C41956A1A RL |
#17
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Behold, legg signalled from keyed 4-1000A filament:
Well, for whatever the reasons, it seems there are no bidders for such critters. http://makeashorterlink.com/?C41956A1A I see. I would think they'd make great SS amp supply filters. *rubs chin* -- Gregg t3h g33k "Ratings are for transistors....tubes have guidelines" http://geek.scorpiorising.ca |
#18
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legg wrote:
On Sun, 19 Dec 2004 11:21:25 -0800, mike wrote: There's a general trend toward INFLATED shipping charges on EBAY. I suspect that fee avoidance is a part of it. Some openly admit to padding their profit. Some buyers seem to lose sight of the total cost and just bid the price up anyway, so it works. A shipping charge 3X what might be considered reasonable and 40X the opening bid is a RED flag. Deception in one area is a good indicator of deception in other areas. I have no information either way about this poster; just speaking generally. The format provided by e-bay makes it difficult to enter an advert without filling in a 'fixed' shiping cost, if origin is non-US. I suppose there are ways to smooth it out, but I have no experience with the format. My research for insured, registered postal service to Australia gave me a Cdn$80 figure; to UK it was Cdn$50. Obviously a customer would likely choose a slower verion, at reduced expense, if he had some confidence in the supplier and was in no great rush. Shipping to US is likely less, but quoting a low 'fixed' rate could obviously create problems for the supplier. I personally prefer standard surface parcel post, which is quite inexpensive, when purchasing. Strangely, some suppliers won't do it that way. While I'm on the soapbox... There's also another interesting trend. Outright lying about the product, either by comission or omission. Let the auction end then disclose the problem. Buyers seem to just pay the inflated price anyway. Most of what I've been involved with has to do with missing or broken "accessory items" that are absolutely necessary to get it to work. I get annoyed when I lose the opportunity to buy a junker at a junker price. Though I haven't bought through e-bay for some years, I've always been suspicious when bid limits were reached but not exceeded - suggesting that someone had a method to probe your limit and get you to pay it, without exposing themselves to the same risk. It's easier to figure out how a last minute bid can beat you by a piddling amount - just takes a well-synchronized clock. Generally it's too expensive to buy junk this way - but lack of other opportunities, andsome luck can nudge ebay's usefulness upwards, for many. RL I found my Dynaco ST70 on ebay for $102.00. It was a great find. Dwaine. |
#19
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On Sun, 26 Dec 2004 10:19:50 GMT, Gregg wrote:
Behold, legg signalled from keyed 4-1000A filament: Well, for whatever the reasons, it seems there are no bidders for such critters. http://makeashorterlink.com/?C41956A1A I see. I would think they'd make great SS amp supply filters. *rubs chin* Do you suppose offering four, might make that a more attractive idea? I'd expected to see at least one bright spark in the audio fringe pondering the possibility of an aluminium-free circuit. All I was trying to do was turn a few of these into cash for an 'authentic' replacement part, needed in a 40yr old amp's repair. The required 40,000uf (3"x3.9") parts don't grow on trees, and I'd never bother to acquire any on spec, as they die 'on the shelf', unlike the tantalums described. ho hum. RL |
#20
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On Mon, 27 Dec 2004 03:40:04 -0500, Dwaine Garden
wroth: I found my Dynaco ST70 on ebay for $102.00. It was a great find. Dwaine. I found my ST70 in a pile of old, used, lab equipment in the hallway of the university where I worked. It was waiting to be taken to the dump. I gave it a new home for the price of picking it up. Jim |
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