不是我做的DIY LPS

cwtim01

由於自己的DIY能力得啖笑，只能做出這隨時電死人的東西：

但這淘寶二十五元的套件也可以為我的CAS帶來可聞的變化，因此早前找Hiendy某師兄做了這個（相片是他在家影的）：

還在煲煉中，但那隨時電死人的東四可以退役了。受到這LPS的影響，決定要試試DIY，訂了這個：

希望不要爆炸。

corolladv

都好靚仔

vpkl

push.........

obee

這個AMB是很好的, 但我覺得它的板子太大塊, 我以前都買過來做DIY. 後來因為板太大又想再做便自己lay板了.
另外, 它網頁上賣的零件都好貴. 如果你做的量多, 可以上RS或者TAOBAO買板上的零件. 價錢會平很多, 運費也慳不少!

cwtim01

obee 發表於 2014-1-13 12:22
這個AMB是很好的, 但我覺得它的板子太大塊, 我以前都買過來做DIY. 後來因為板太大又想再做便自己lay板了.
...

Thank Obee ching for the tips.

I just ordered several boards and plan on buying components from Digikey or RS. I'm also very interested in buying components from TaoBao, but I find there is a huge price difference between TaoBao shops and Digikey, so big so that I'm wondering if the components from TaoBao are authentic ones.

Is there any trustworthy TaoBao shops you could recommend.

obee

cwtim01 發表於 2014-1-13 14:00
Thank Obee ching for the tips.

I just ordered several boards and plan on buying components from D ...

Check PM.

The most expensive parts is the current diode, E-202 and E-502. The rest are cheap.
I've ordered say 40 sets and using. So far only 1-2 set not working, I no time to de-solder to check which one is faulty and I just de-solder the capacitors and throw away the board whenever there is problem.

edison133

good try, looking for your update post!

obee

AMB 我做左兩個 size:
細電流用的(5cm X 5cm), 可放在細箱內:


大電流用的(5cm X 10cm), 給NAS用:

cwtim01

obee 發表於 2014-1-15 09:48
AMB 我做左兩個 size:
細電流用的(5cm X 5cm), 可放在細箱內:

Very impressive that you’ve shrunk the board to a quarter of the original size. In fact I’m also planning on making a high current one for my NAS, but need some help about component selection to enable high current:

• Toroidal transformer, diode and FET – I suppose I can just refer to the datasheet;
• Output resistor – I see that you’ve used two 5W ones, is the formula: “P = (I/2)^2 * R” a good approximation to select the rating?
• Electrolytic capacitor – this is the one I struggle with. If I want to, say, enable a 7.5A output current, I’m not sure what capacitor values to be used (it’s not very scientific to just throw in a 10000uF and hope it’s enough. – Could you give some hints.

One more question, for those 220pF ceramic capacitors, is it ok to replace them with other types of capacitor, as long as they’re non-polar (asking as it’s very difficult to find a TaoBao shop to have everything I need). Thanks !!

obee

cwtim01 發表於 2014-1-15 14:15
Very impressive that you’ve shrunk the board to a quarter of the original size. In fact I’m also ...

First of all, I am not knowledgeable enough to answer all these are my major was not electronic/electrical engineering. I just share my experience as a player who still alive.

Toroidal transformer, diode and FET – I suppose I can just refer to the datasheet;

My suggestion is, as large as possible. If your actual rating is 50W, make 100W toroidal transformer or above.

Output resistor – I see that you’ve used two 5W ones, is the formula: “P = (I/2)^2 * R” a good approximation to select the rating?

Yes. Use this formula is okay.

Electrolytic capacitor – this is the one I struggle with. If I want to, say, enable a 7.5A output current, I’m not sure what capacitor values to be used (it’s not very scientific to just throw in a 10000uF and hope it’s enough. – Could you give some hints.

As I know, there's relationship between the ripple, frequency, load current and capacitance:
http://www.radio-electronics.com ... acitor-circuits.php
Note that (I guess u know already) the capacitor will get hot as load current rise, so use 105 degree is preferred for large load current application.

One more question, for those 220pF ceramic capacitors, is it ok to replace them with other types of capacitor, as long as they’re non-polar (asking as it’s very difficult to find a TaoBao shop to have everything I need).

I have no idea. Some people say that using larger capacitance or large 耐壓 always ok and always better. But you know it is just for filtering purpose for diode, so I think the capacitance value is highly depends on the type of diode it is bypassing and the current load. As you see, I did't follow the original part list, this is because the difficulty of sourcing.
For more info, check this:
http://www.diyaudio.com/forums/s ... -rectifiers-do.html

hksarac

請問cwtim01 師兄，這套電源成品/套件是在那裡訂購的。

cwtim01

hksarac 發表於 2014-2-2 09:29
請問cwtim01 師兄，這套電源成品/套件是在那裡訂購的。

Hi hksarac ching, you can order the board here:

http://www.amb.org/audio/sigma11/

But they don't offer full kits and you have to purchase the components yourself. As mentioned by Obee ching, Taobao is the cheapest if you buy in large volume, but you have to buy from multiple shops and shipment cost can be expensive for small volumes. Otherwise http://hk.element14.com/ is a good all-in-one shop to buy from, and they offer free shipment for relatively small orders.

My testing Sigma 11 here:

Didn't expect my first serious soldering exercise in 15 years to work (last time was making 8088 CPU boards back in college), but it actually works. Still need to drill some holes to make it a functioning unit though.

cwtim01

Apparently another ching is organizing a group buy of the Sigma 11 board:

http://www.hiendy.com/hififorum/ ... page%3D1&page=2

hksarac

thanks cwtim01 ching

hevenktc

cwtim01 發表於 2014-2-2 21:33
Hi hksarac ching, you can order the board here:

http://www.amb.org/audio/sigma11/

師兄, 你隻PSU output係幾多V及幾多A?

krell

hevenktc 發表於 2014-2-13 23:15
師兄, 你隻PSU output係幾多V及幾多A?

但小心，FE丅在大電流時會好熱，安在殻會好D

hevenktc

krell 發表於 2014-2-14 00:00
但小心，FE丅在大電流時會好熱，安在殻會好D

Krell 師兄, 我對電子一知半解, 我so far 裝電腦部件就OK, 所以見到你個PSU內部相對易接駁, 所以問可否跟隨你們的hardware list copy one to DIY the PSU! 而你所提及的FET, 就不知是什麼! 如果好似砌電腦的, 有齊部件及manual, 咁就易辦啦? 同時如果有師兄訂開, 我希望可以跟單, 咁就最好啦

krell

hevenktc 發表於 2014-2-14 00:33
Krell 師兄, 我對電子一知半解, 我so far 裝電腦部件就OK, 所以見到你個PSU內部相對易接駁, 所以問可否跟 ...

hevenktc兄，如果你沒有電子底，不知原子粒，FET是什麼，怎分腳位，但又想DlY的話，建議倒不如上amb網購買它的套件成品好過，若用萬用板砌的話，沒有電子底會難上加難，倒不如砌成品套件加外殻成功機會會高些，但火牛那部份始終要接220V，可要小心一點。

hevenktc

krell 發表於 2014-2-14 09:47
hevenktc兄，如果你沒有電子底，不知原子粒，FET是什麼，怎分腳位，但又想DlY的話，建議倒不如上amb網購 ...

Krell 兄,
建議倒不如上amb網購買它的套件成品好過 --> 咁就相對簡單!

Thanks a lot for your useful info.

cwtim01

Hi,

I have quite a few spare boards from AMB (I order 10 in one shot, and now change my mind and want to try making my own like Obee ching), so happy to part with some of them, interested one can send me a PM.

I even have most of the key components required and can bundle them , maybe except the diodes as I got those exotic CREE diodes which is probably too expensive to justify.