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Post by rod on Feb 5, 2005 17:19:08 GMT
My ignorance is showing again... I now have my Scott Nixon dac-kit pcb I don't have a clue about capacitors You guys can help! ;D (PS. I could ask Scott, but the reply might take a little while, considering how busy he is) The stuffing guide is of no real help to me. So my questions are: - 1) Cap value versus voltage - Scott recommends Panasonic FC's for the following values - 100uf - 220uf - reg output 1000uf - DC input filtering What voltage values should I be looking at? For example, when I tried RS for these caps, the 220 / 6.3v is out of stock, but they recommend using a 10v Rubycon - is that ok? Is 6.3v ok in the first place?!!! 2) A 47uf Black Gate NX NP for output coupling caps or Rubycon ZA. Where can I buy either of these, and which voltage value? 3) The 0.01uf and 0.47uf caps appear to be those little block-shaped caps (is that a technical term? ). Same again, what type are they, polyprop? and if so what voltage value. At least there's one thing, when this lot gets answered, not only will I be able to order stuff for my DAC, but I will know a bit more about cap values Oh... there's more... 4) "Small single-section Exclusive OR (surface mount) - what on earth do I order here? 5) I need a couple of LEDs - any particular voltage, etc? Still, all this keeps me out of trouble ;D
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Alick
<100
The Fife Panther strikes again!
Posts: 41
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Post by Alick on Feb 5, 2005 19:31:35 GMT
1. We probably need more info but I would generally recommend a voltage value 50% to 100% greater than the maximum you would expect the component to be subjected to. You haven't told us where the 100uF is in the circuit and I'm guessing that the 220uF and 1000uF are associated with the power supply side of things, so the supply voltage should give you a clue there.
2. Mike might be able to point you in the direction of a stockist for Black Gates; I've never used them. NP stands for non-polarised. I'd be tempted to use the OSCONs available from Rapid Electronics, the ALCAPs from Cricklewood Electronics or the Natai's from WNA.
3. Polyprops should be fine, but again we haven't seen the schematic.
4. I'm not certain, but SMD capacitors are available from Rapid. Where does this one go?
5. LED's will work in pretty much any DC situation. You just need to know what current they require for normal illumination and calculate a suitable resistor to put in series with it. Current (I) = Voltage (V)/Resistance (R) (this is Ohm's law) so if the LED is rated at 10mA and the voltage is 12 V you need a 12/.01= 1200 ohm (1K2) resistor.
I hope this helps?
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Post by PinkFloyd on Feb 5, 2005 20:04:08 GMT
1) Cap value versus voltage - Scott recommends Panasonic FC's for the following values - 100uf - 220uf - reg output 1000uf - DC input filtering What voltage values should I be looking at? For example, when I tried RS for these caps, the 220 / 6.3v is out of stock, but they recommend using a 10v Rubycon - is that ok? Is 6.3v ok in the first place?!!! Haven't seen the schematic Rod so I haven't got a clue what voltage / values you should be using but let's assume one of the caps is 100uF 35V, it's ok to select a higher voltage cap in place of it (ie: 100uF 100V) but under no circumstances go under the recommended voltage. If you can point us to the schematic then we can help you choose the appropriate parts. 2) A 47uf Black Gate NX NP for output coupling caps or Rubycon ZA. Where can I buy either of these, and which voltage value? You can get the non polar blackgates from www.audionote.co.uk/ or you can get great sounding Nitai non polars from www.rapidelectronics.co.uk/rkmain.asp?PAGEID=80010&CTL_CAT_CODE=31198&STK_PROD_CODE=M62536&XPAGENO=1 the Nitais are good caps and a truckload cheaper than the blackgates. 3) The 0.01uf and 0.47uf caps appear to be those little block-shaped caps (is that a technical term? ). Same again, what type are they, polyprop? and if so what voltage value. They sound like polyprops but, again, without seeing the schematic I can't advise you on values. 4) "Small single-section Exclusive OR (surface mount) - what on earth do I order here? Another case of "schematic please" 5) I need a couple of LEDs - any particular voltage, etc? www.rapidelectronics.co.uk/rkmain.asp?PAGEID=80010&CTL_CAT_CODE=&STK_PROD_CODE=M29324&XPAGENO=1 if it's a 24V supply then whack a 5K1 resistor in series with the anode leg of the LED. LED and BEZEL here, these are great and sometimes work out cheaper than buying the LED alone: www.rapidelectronics.co.uk/rkmain.asp?PAGEID=80010&CTL_CAT_CODE=&STK_PROD_CODE=M29277&XPAGENO=1
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Post by PinkFloyd on Feb 5, 2005 20:41:47 GMT
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Post by rod on Feb 5, 2005 23:36:59 GMT
I understand that the schematic would be useful, however, my scanner is deceased. I am also a bit wary of Scott's IPR, since he doesn't have a copy online, would it be naughty to post a schematic? "but I would generally recommend a voltage value 50% to 100% greater than the maximum you would expect the component to be subjected to." Cheers Alick, that's the kind of info I'm looking for. The dac uses a 12vdc input (3 to 4v at dac output) - so I'll need a psu as well, I must have a few of these lying around. (Wonders - Would it be possible to build a psu to supply both the wnaha and this dac? Hmmm) Given that the board layout diagram shows a 47uf Cap, states that a "4700/16v" cap is optional. That is at the ouput end. Would this mean that 16v or 25v caps would be ideal for the others? I have since found that hificollective have a stock of black gates, now that Rubycon have ceased production of BGs. Thanks to both of you for the info and supplier details. I'm happy with polar / non-polar caps. Cool for the LEDs now. Thanks for the link. I know about AND / OR / NOR / EXOR, etc. gates but have never come across them in practice, this is for the phase correction (optional). Mike, that's the dac in your picture. The main exception is that I have the tiny smd CS8414 instead of the pictured CS8412. No point making things easy for myself! Think I'll get a silver Hammond to match the wnaha. There's not really much to it! I should be able to scan this on Monday and maybe send directly rather than posting. Thanks for the help guys, I appreciate it!
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Post by rod on Feb 6, 2005 20:33:19 GMT
Regarding polyprop caps- The ones I have seen all seem to have a much higher working voltage spec than is likely to be found on the pcb (whereas the electrolytics have a wide range). What should be taken into consideration when choosing a polyprop? (Given that you don't have the schematic yet ) PS. I forgot to check Farnell when searching for stuff, they have a better range of caps than RS / Rapid / Maplin.
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Alick
<100
The Fife Panther strikes again!
Posts: 41
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Post by Alick on Feb 6, 2005 22:07:25 GMT
ISTR that Farnell have a fairly high minimum order value.
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Post by PinkFloyd on Feb 7, 2005 0:06:38 GMT
Farnell are best avoided....... BANDITS
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Post by rod on Feb 7, 2005 7:11:29 GMT
Ooops! What happened Mike.
Alick, £20 min order on credit card.
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Alick
<100
The Fife Panther strikes again!
Posts: 41
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Post by Alick on Feb 7, 2005 8:10:38 GMT
Mike had a bad experience with some faulty potentiometers, the details of which are near the beginning of the original WNA mega-thread of Head-Fi (BTW Mike, I see you got your time off for good behaviour ). I've never been a big fan of Farnell either.
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Post by rod on Feb 7, 2005 18:11:57 GMT
Ahhh! I seem to remember that one now. Tossers! I clean forgot to scan the schematics today, will have to do it tomorrow.
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Post by rod on Feb 7, 2005 20:29:54 GMT
Hi again. For your information, Scott answered my e-mail pretty quickly. My Questions and Scott's answers: - 1) Cap value versus voltage - You recommend Panasonic FC's for the following values - 100uf - 220uf - reg output 1000uf - DC input filtering What voltage values should I be looking at? For example, when I tried RS for these caps, the 220 / 6.3v is out of stock, but they recommend using a 10v Rubycon - is that ok? Is 6.3v ok in the first place?!!! 100 and 200 as well as output caps can be 10V. Whatever is small and will fit.
1000 is usually 25V2) A 47uf Black Gate NX NP for output coupling caps or Rubycon ZA. Which voltage value? 10V or better3) The 0.01uf and 0.47uf caps appear to be polyprops? and if so what voltage value. Whatever will fit the lead spacing. these see around 5v so anything 6.3v or better4) The optional large Cap - 4700/16v - Can I just drop one in, or is this dependant on something else? just use 1000uf there 16/25v somthing skinny as it's between 2 regs. 5) Can you give me an idea what I should order for the "small single-section Exclusive OR smd". Can't help you there, as I have no idea what your vendors would have.
Just go inverted and not worry about it.Good man! However, I could do with some clarification on what to order for the little polyprops, given that Scott has mentioned 6.3v or better. I couldn't seem to find anything lower than 100v. Also I could have done with an answer on the XOR. The electrical guys at my place of work made a few suggestions, but nothing that will fit in that space! Anyway, if someone can help out with the polyprop bit, I'll place an order. Off on business this weekend, so I probably won't be starting until the following weekend. I will need to think carefully about what I really want from a preamp, as Mike's suggestion for a case (Galaxie) has really got me thinking about my pre / dac / headamp idea. Maybe with a psu in a matching case. Hmmm! Knowing me, this will take quite a while. ;D
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Post by rod on Feb 9, 2005 18:00:32 GMT
Mike
You have mail
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Post by rod on Feb 16, 2005 16:29:48 GMT
Any help on the polyprop caps value thing appreciated, I have just received the CS8414, and I will need to order the other stuff now.
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Post by audioray on Nov 26, 2005 2:05:51 GMT
hi im in boston mass. where do you buy the RIFA caps. from thank you
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Post by PinkFloyd on Nov 27, 2005 23:19:52 GMT
hi im in boston mass. where do you buy the RIFA caps. from thank you Hi Ray. www.rswww.com part number 414-7670 that should bring you to the Rifa caps. Mike.
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