論壇 › DIY分享 › 求DACmagic環牛一隻,小弟對電子野完全唔識,又唔想浪費左部機

royccw 發表於 2011-4-13 12:54

It the market there are two common outpur terminal

1) 12V - 0V - 12V (3 wires)
2) 12V - 0V      12V - 0V (4 wires, ie. two independ use o/p)

For (2) there are two indpendent 0V that mean you can seperate two set of output with two difference ground.
If you want to increase output current so that you can connect in parallel (i.e. 12V wire connect to 12V, 0V wire connect to 0V). One of the drawback is that output terminal may not exact same voltage so there may not balance in loading.

sunboy 發表於 2011-4-13 16:21

Thanks for royccw & derekwyw C Hing's reply and advice {:1_347:}

royccw C Hing, would you connect the both 12V cables in parallel for higher power current (I want to see if it will be better for sonic performance) or just use them individually for 2 outputs if you were me ?

On the other hand, can I put a select switch to switch over between high power and standard power output for trial ?

Can you teach me how to find out which wire is 0V and 12V (by multi-tester ?) so that I can try myself if the above suggestion is possible ?

Sorry for my stupid as I'm only a newbie in electronic..........{:6_136:}

Thanks for your help in advance{:1_347:}

derekwyw 發表於 2011-4-13 17:16

隻牛上面有寫邊條係+12v邊條係0v

Kyo-Mok 發表於 2011-4-13 20:15

隻牛上面有寫邊條係+12v邊條係0v
derekwyw 發表於 2011-4-13 17:16 http://www.post76.com/discuss/images/common/back.gif


    隻牛上面既係交流, 要經整流之後先會出+V & -V.
一般情況下, 全橋整流後既電壓(VDC) = VAC x 1.414 (忽略晶體管、線圈內阻)
半橋整流就 x 0.707

derekwyw 發表於 2011-4-14 10:10

回復 34# Kyo-Mok
yr

謝謝分享呵~能說一下全整流和半整流的分別嗎~另用電子牛的bd機可以改環牛嗎{:6_240:}

royccw 發表於 2011-4-14 10:25

本帖最後由 royccw 於 2011-4-14 10:26 編輯

Thanks for royccw & derekwyw C Hing's reply and advice

royccw C Hing, would you connect t ...
sunboy 發表於 2011-4-13 16:21 http://www.post76.com/discuss/images/common/back.gif

    Hi Sunboy,

I have your RS recommend Transformer, they have spec to be downloaded to find out which colour represent which output.

http://docs-asia.electrocomponents.com/webdocs/0028/0900766b800284c0.pdf
How much power do you need? For me I would not parallel those output in order to increase power. I prefer to choose high power
one and use only side, another side use for DC output to drive CD player/HeadAMP etc.
Reminded that if you decide to use only one side of output, it only provide 1/2 of total transformer rating so be careful of choosing right transformer.

List up what is your requirement so that we can help more easily
example :
Input : AC220
Output : AC xx volt
             DC xx volt
Output Power/Current : ???

Kyo-Mok 發表於 2011-4-15 16:27

回復Kyo-Mok
yr

謝謝分享呵~能說一下全整流和半整流的分別嗎~另用電子牛的bd機可以改環牛嗎 ...
derekwyw 發表於 2011-4-14 10:10 http://www.post76.com/discuss/images/common/back.gif


    簡單來講, 全橋整流用四個二極管, 半橋只用兩個. 由於半橋整流只對交流作半個周期以下既導通, 理論上可得到既直流電壓只有全橋既一半.
switching psu換環牛理論上可行, 只要部機唔係軟開機電路.
但用起BD機, 以我經驗, 如果全機都用環牛, 無論聲定畫, 效果都必定比只用switching psu差N條街. 誇張D講, BD → DVD.
可考慮將analog部分改用環牛/R牛 + 穩壓, 用relay實現軟同步開機. 但要小心唔好同隻switching psu既供電線路並接. (ground除外)

royccw 發表於 2011-4-16 22:21

求DACmagic環牛一隻,小弟對電子野完全唔識,又唔想浪費左部機

    簡單來講, 全橋整流用四個二極管, 半橋只用兩個. 由於半橋整流只對交流作半個周期以下既導通, 理論上可得到既直流電壓只有全橋既一半.
switching psu換環牛理論上可行, 只要部機唔係軟開機電路.
但用起BD機, 以我經驗, 如果全機都用環牛, 無論聲定畫, 效果都必定比只用switching psu差N條街. 誇張D講, BD → DVD.
可考慮將analog部分改用環牛/R牛 + 穩壓, 用relay實現軟同步開機. 但要小心唔好同隻switching psu既供電線路並接. (ground除外)
Ching 可真考慮清楚去改部BD 機，因為BD 機電源比起CD／DVD 複雜，也有一些standby 功能，最麻煩係有些需要MCU 控制每set 電源開始時間。我到現在都未見過BD 機用環牛或及R -core 反而高級CD/DVD 就有見過。


- 發送自我的 iPhone

derekwyw 發表於 2011-4-18 23:14

回復 38# royccw


    謝謝~所以想很久都沒動手{:6_123:}

derekwyw 發表於 2011-4-18 23:15

回復 37# Kyo-Mok


   謝謝提點

查看完整版本: 求DACmagic環牛一隻,小弟對電子野完全唔識,又唔想浪費左部機