I am in the process of replacing electrolytic capacitors in a 1960's Japanese tube receiver (AGS-Trio KW55) and have a bit of a quandary. I purchased replacement electrolytics from a list prepared by recording the values of the original ones while still in circuit. And then I went shopping.
Up to now, a quantity of replacements have been done with more or less satisfactory results meaning the amplifier section of the receiver works better than it did but I halted when I got to these two.
One is a bi-polar 50V 2uF cap and the other a 50V 20uF polarized.
The new ones I bought are 50V 2.2uF and 50V 22uF respectively.
But the replacements are a lot smaller physically that those I wish to replace.
I understand it is quite normal and expected for modern caps to be smaller than similar value ones from 50 or so years ago but the disparity here makes me uncomfortable.
Something that enforced my concern was what was printed on the original 2uF bi-polar cap. It is labeled 50WV-working volts and 75SV- surge volts.
My replacements are branded Elna and labeled @ 50V but the data sheet I looked over did not state what the maximum allowable voltage was that they could be subjected to for a brief time. Either that or I could not understand what I was reading.
My hope is that someone can either tell me to put the brakes on and find something else or validate that what I have will be appropriate.
Up to now, a quantity of replacements have been done with more or less satisfactory results meaning the amplifier section of the receiver works better than it did but I halted when I got to these two.
One is a bi-polar 50V 2uF cap and the other a 50V 20uF polarized.
The new ones I bought are 50V 2.2uF and 50V 22uF respectively.
But the replacements are a lot smaller physically that those I wish to replace.
I understand it is quite normal and expected for modern caps to be smaller than similar value ones from 50 or so years ago but the disparity here makes me uncomfortable.
Something that enforced my concern was what was printed on the original 2uF bi-polar cap. It is labeled 50WV-working volts and 75SV- surge volts.
My replacements are branded Elna and labeled @ 50V but the data sheet I looked over did not state what the maximum allowable voltage was that they could be subjected to for a brief time. Either that or I could not understand what I was reading.
My hope is that someone can either tell me to put the brakes on and find something else or validate that what I have will be appropriate.
Attachments
I've attached a copy of the IEC testing paragraph relating to surge voltage.
Basically it is 1.15x the rated voltage.
I would personally work on the rated voltage being the upper limit of voltage that I expect a capacitor to endure, unless the datasheet specifically states otherwise.
Your example capacitor has an SV of 75v so I'd choose a value above the 75v.
I'd use something like this one which is 20uF 100v: Mouser Electronics, Inc. Australia
Or something like this 22uF 80v which is cheaper: 870056175003 Wurth Electronics | Mouser Australia
Depends on the application within the circuit too, as to how much $$ I'd spend and what manufacturer/series I'd use.
Basically it is 1.15x the rated voltage.
I would personally work on the rated voltage being the upper limit of voltage that I expect a capacitor to endure, unless the datasheet specifically states otherwise.
Your example capacitor has an SV of 75v so I'd choose a value above the 75v.
I'd use something like this one which is 20uF 100v: Mouser Electronics, Inc. Australia
Or something like this 22uF 80v which is cheaper: 870056175003 Wurth Electronics | Mouser Australia
Depends on the application within the circuit too, as to how much $$ I'd spend and what manufacturer/series I'd use.
Attachments
Yes, you and the previous respondent agree on this and it does makes sense. To a degree I am fortunate in having an electronics parts store somewhat nearby. I makes the cash outlay for parts much less than online ordering. No shipping charge and no Canadian to US currency exchange.
I do see 22uF electrolytics on their website of perhaps 400V and is not overly expensive. I'll pick one up - hopefully there will be enough room (without the original in place) for it to fit in.
Being bi-polar's are less common, I may just use those small ones I have and see what happens.
New tech caps are 1/4 size of old tech caps.
Elyt cap is not a reputed brand of electrolytic cap. I've gotten good results out of Panasonic, Nichicon, Rubicon, Vishay. 2nd level of quality because of the higher ESR allowed at their end of life test, United Chemicon, CDE, Multicomp. I've installed over 300 e-caps in the last 11 years in audio gear organs & radios. So far no repeat failures.
I don't like doing this job over & over as I did when I was buying e-caps at the TV parts store. My ST70 I've replaced the caps 4 times. From Farnell, Mouser, Digikey, I can order caps with a service life rating fo 3000 hours (big caps) or 10000 hours (47 uf & down). 500 service life hour caps are available from the premium brands, and prof service shops love them for the repeat business: don't get caught in that trap. Once the cap is out of the printed labeled bag, you can't tell what the service life is without testing one to too much hum. (life test). If you have actual parts number on your invoice, you can look that up by downloading datasheet from farnell, mouser, digikey: Or occasionally datasheetcatalog.com
Be aware when ordering from farnell, they bounce to the US warehouse people report. In that case be SURE to specifiy US mail/ royal mail as delivery method. UPS & Fed Ex charge a $40 loan origination fee for the customs charge of maybe $1.
Digikay trucks across the US border privately & mails inside canada for no customs.
In the case of a 2 uf bipolar cap, a mylar cap would probably fit, and polyprophylene might sound a little better. Lower voltages are smaller but a little hard to find. 63 v is pretty commonly stocked. New value will be 2.2 uf. If the 10% mismatch is critical you can parallel a 1.5 uf cap and a 0.47 uf cap.
Elyt cap is not a reputed brand of electrolytic cap. I've gotten good results out of Panasonic, Nichicon, Rubicon, Vishay. 2nd level of quality because of the higher ESR allowed at their end of life test, United Chemicon, CDE, Multicomp. I've installed over 300 e-caps in the last 11 years in audio gear organs & radios. So far no repeat failures.
I don't like doing this job over & over as I did when I was buying e-caps at the TV parts store. My ST70 I've replaced the caps 4 times. From Farnell, Mouser, Digikey, I can order caps with a service life rating fo 3000 hours (big caps) or 10000 hours (47 uf & down). 500 service life hour caps are available from the premium brands, and prof service shops love them for the repeat business: don't get caught in that trap. Once the cap is out of the printed labeled bag, you can't tell what the service life is without testing one to too much hum. (life test). If you have actual parts number on your invoice, you can look that up by downloading datasheet from farnell, mouser, digikey: Or occasionally datasheetcatalog.com
Be aware when ordering from farnell, they bounce to the US warehouse people report. In that case be SURE to specifiy US mail/ royal mail as delivery method. UPS & Fed Ex charge a $40 loan origination fee for the customs charge of maybe $1.
Digikay trucks across the US border privately & mails inside canada for no customs.
In the case of a 2 uf bipolar cap, a mylar cap would probably fit, and polyprophylene might sound a little better. Lower voltages are smaller but a little hard to find. 63 v is pretty commonly stocked. New value will be 2.2 uf. If the 10% mismatch is critical you can parallel a 1.5 uf cap and a 0.47 uf cap.
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The only free shipping from Mouser/Digikey in Canada is for orders over $100.
The least expensive option for either is $8 for orders under $100.
Arrow offers free shipping on any value order,but unfortunately uses Fedex for shipping to Canada,who will then extort two to three times the order value in ''brokerage fees''.
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Regarding comment above Elna is a very reputable Japanese brand. (They did have the misfortune of being widely copied and incorrectly so by a number of other manufacturers in the far east.) I guess here at home I have used several thousand EL caps over the past decade and in my daily job have specified parts used in the millions.
> 62vauxhall
Your username implies you may know a 1962 Vauxhall had a 1500cc engine which was rated 50 horsepower. We have a 1991 MX5 Miata with a 1600cc engine rated (IIRC) 115HP. Looking around, today's 1.5L engines claim 170HP and more (with turbo). Or conversely, for similar power, engines a couple decades back were 2.5-3.3L and now 1.5-1.8L. We find a 3.8L V6 in large pickup trucks we always powered with 5.7-7L V8s.
The technology finds ways to put more stuff in smaller bags.
Your username implies you may know a 1962 Vauxhall had a 1500cc engine which was rated 50 horsepower. We have a 1991 MX5 Miata with a 1600cc engine rated (IIRC) 115HP. Looking around, today's 1.5L engines claim 170HP and more (with turbo). Or conversely, for similar power, engines a couple decades back were 2.5-3.3L and now 1.5-1.8L. We find a 3.8L V6 in large pickup trucks we always powered with 5.7-7L V8s.
The technology finds ways to put more stuff in smaller bags.
Hard to believe, but it's true. Dirt cheap, though. And what a warranty.
China Rukycon Aluminum Electrolytic Capacitors 100V470uF 16*27 mm, Router, switching Power supply, fan on Global Sources
"If the item you purchase from factory beacuse of quality problems, you can return them to us
for replacement or refund. And any items returned must be in their original condition to qualify
for a refund or replacement."
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Too late to backtrack as all but two capacitors are soldered in.
I'm not overly concerned about the pedigree of components purchased from this local vendor. I did not study the logo so was unaware that one of the letters may have been slurred. In my mind, it could just as easily be a bad printing run of the plastic wrappers.
My parts purchasing is by comparison modest I'm sure. Likely three or four hundred dollars per year, maybe not even that. The only defective part I received from there was one of several TO3 transitors. That was about two years ago. But capacitors comprise most of my component purchases. Rubycon is the brand I've seen there most frequently followed by a good number of Nichicon and Panasonic.
One time, when there was considerable forum discussion about fake parts made in China, I asked the owner's son if that's what they sold. It happened to be Rubycon I was asking about. It was explained that they were genuine but China is now where the bulk of such things originate from. It made sense to me that established makers of such mass produced items would take advantage of low manufacturing costs where an infrastructure already exists making like kind products. I've read speculation that the majority of, capacitors for instance, are now made in China regardless of brand. And I believe I've also read that TI parts now all originate in China.
The proprietor of the shop in question is Chinese and has had that business since 1993. Currently he has no competition and all the techs I've conversed with have purchased there themselves. But, they also have accounts with the biggies, Mouser, Digikey, Newark and likely others. The local shop carries mostly the mainstays and often does not have things on hand that I've been needing. Sometimes, they've offered to do special orders and I've availed myself of that option.
I don't require parts often enough or in large enough quantities to justify online orders, especially if the cost is only going to be a buck or two, so having a local outlet that satisfies 90% of my wants on an as needed basis is very convenient and cost effective. There is no currency exchange, shipping or potential duty & taxes to contend with.
Up to about two years ago there was another parts business which has been around at least since the 1970's. Those owners were a non-Chinese family.
That was my preferred store for a long time because of all the NOS obsolete parts I could find there. It was also the store I was cautioned on by a few techs. The warning had to do with semi-conductors they sold - apparently blatant forgeries.
I thought it was ironic that bad Chinese copies originated from a non-Chinese owned business yet the Chinese owned one had not been cited as offending in that regard.
I'm not overly concerned about the pedigree of components purchased from this local vendor. I did not study the logo so was unaware that one of the letters may have been slurred. In my mind, it could just as easily be a bad printing run of the plastic wrappers.
My parts purchasing is by comparison modest I'm sure. Likely three or four hundred dollars per year, maybe not even that. The only defective part I received from there was one of several TO3 transitors. That was about two years ago. But capacitors comprise most of my component purchases. Rubycon is the brand I've seen there most frequently followed by a good number of Nichicon and Panasonic.
One time, when there was considerable forum discussion about fake parts made in China, I asked the owner's son if that's what they sold. It happened to be Rubycon I was asking about. It was explained that they were genuine but China is now where the bulk of such things originate from. It made sense to me that established makers of such mass produced items would take advantage of low manufacturing costs where an infrastructure already exists making like kind products. I've read speculation that the majority of, capacitors for instance, are now made in China regardless of brand. And I believe I've also read that TI parts now all originate in China.
The proprietor of the shop in question is Chinese and has had that business since 1993. Currently he has no competition and all the techs I've conversed with have purchased there themselves. But, they also have accounts with the biggies, Mouser, Digikey, Newark and likely others. The local shop carries mostly the mainstays and often does not have things on hand that I've been needing. Sometimes, they've offered to do special orders and I've availed myself of that option.
I don't require parts often enough or in large enough quantities to justify online orders, especially if the cost is only going to be a buck or two, so having a local outlet that satisfies 90% of my wants on an as needed basis is very convenient and cost effective. There is no currency exchange, shipping or potential duty & taxes to contend with.
Up to about two years ago there was another parts business which has been around at least since the 1970's. Those owners were a non-Chinese family.
That was my preferred store for a long time because of all the NOS obsolete parts I could find there. It was also the store I was cautioned on by a few techs. The warning had to do with semi-conductors they sold - apparently blatant forgeries.
I thought it was ironic that bad Chinese copies originated from a non-Chinese owned business yet the Chinese owned one had not been cited as offending in that regard.
The 'Rukycon' cap will probably work fine so long as its not taken too close to its working voltage. The problems I've had with dodgy Chinese cap brands has been mostly in terms of the stated working voltage not being honoured in practice, together with tolerances being way too generous (in the negative direction always).
My habit has generally been to go at least one voltage step higher with replacement over original caps so I'm reasonably confident of being above borderline. The odd time out of necessity, I've stayed at original voltage (never less) if there's nothing higher that has the required value.
If I am skunked, as in cannot obtain such an item conveniently, it is then when I go to the online vendors.
If I am skunked, as in cannot obtain such an item conveniently, it is then when I go to the online vendors.
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