音響發燒網 HiFi Fever

Fever DIY DIY天地 :: RE: DIY Marantz 7C

solderman — Sat, 17 May 2008 14:11:52 GMT

發表人: solderman
發表於: 2008-05-17 (星期六) 10:11 pm (GMT 8)

This link may be useful for you http://www.bbc163.com/read.php?tid=2961
I think this board is come from this company.

Fever DIY DIY天地 :: New Marantz 7C problems

alfcat — Sat, 17 May 2008 13:21:07 GMT

發表人: alfcat
主題: New Marantz 7C problems
發表於: 2008-05-17 (星期六) 9:21 pm (GMT 8)

Dear Accphoto,

Do I have the wires and everything connected right? Please help. Many thanks. I don't need to connect the 9 pin of the 12AX7, right?

AND most importantly, how do I Ground (yellow green wire) the output section? Should I change the power connector to a FIVE pins one instead of the current Four pins (310 V AC + 13 V AC now)?

CAT

Fever DIY DIY天地 :: RE: DIY Marantz 7C

alfcat — Sat, 17 May 2008 13:13:59 GMT

發表人: alfcat
發表於: 2008-05-17 (星期六) 9:13 pm (GMT 8)

Dear alant,

Oh, your son is lucky then. I don't teach as many class as before. If he is in Science class (in the future), then the chance of him seeing me is minimal.

Usually I am very cautious about High Voltage, although I got 9 lives.

CAT

Fever Club 發燒同好會 :: RE: Marantz AV Amp SR-5200

laukcr — Sat, 17 May 2008 11:36:38 GMT

發表人: laukcr
發表於: 2008-05-17 (星期六) 7:36 pm (GMT 8)

Cheapie, 如果我建議向你租用SR5200 Remote幾天, 有得傾嗎? Thanks!!

Fever Club 發燒同好會 :: RE: 元朗發燒同好會

keniche — Sat, 17 May 2008 07:26:36 GMT

發表人: keniche
發表於: 2008-05-17 (星期六) 3:26 pm (GMT 8)

搞錯了,去了主題,請去望望。

Fever Club 發燒同好會 :: 元朗發消同好会,Ewel,亞洛

keniche — Sat, 17 May 2008 07:24:25 GMT

發表人: keniche
主題: 元朗發消同好会,Ewel,亞洛
發表於: 2008-05-17 (星期六) 3:24 pm (GMT 8)

我又少了來了,Ewel比心機「沖厠」呀！考好Ｄ,試完再來打搞,吾介意亞洛都來麻，兩個都係年青人，我變左老餅咯,亞洛住元朗邊度？Ｄ歌有無聽到白光、李香籣、周璇咁老呀？我除了蔡琴,近日聽陳潔麗,中樂,交响樂多Ｄ,近來部M有Ｄ問題，你董DIY的,可以幫手唸唸嗎？我Ｄ都係普通野。

Fever DIY DIY天地 :: RE: DIY Marantz 7C

alant — Sat, 17 May 2008 06:30:10 GMT

發表人: alant
發表於: 2008-05-17 (星期六) 2:30 pm (GMT 8)

alfcat 寫到:

Dear alant,

I don't mind at all. I come here to learn and any advice is welcomed.

Yes, I am in that school. If your son happened to be in 1E, 3E, 5A, 6A or 7A, I am his teacher then. If your son is not is any of these classes, then your son is VERY LUCKY ... ha..ha.

CAT

Dear CAT sir,

I have two sons. The younger one is studying in primary while elder one is studying in secondary school at same “brand name” of your school. I have asked my son and he replied that you have not taught him yet. May be later! Your expertise is Economic. Enjoy your hobby here with technical guidance from experienced people, but beware of the safety in electrical precaution. I am also an audio DIY beginner. I also don’t understand many HiFi circuit design and need to learn more.

B. regards,
alant

Fever DIY DIY天地 :: RE: DIY Marantz 7C

alfcat — Sat, 17 May 2008 05:07:46 GMT

發表人: alfcat
發表於: 2008-05-17 (星期六) 1:07 pm (GMT 8)

Oh, I thing I haven't fully understand yet. The Matisse Rectifying board (when not connected to the M7 output stage board) yields an output voltage of 309V DC. Now, this is an "Open Circuit", right?

So, if I want the "True" measurement, I should connect the M7 output stage board to this Rectifying board, plug in the 12AX7 TUBES and then measure the voltage at B1+ and B2+ to see if they are 280V DC and 260V DC respectively.

Am I correct? Don't want to blow the whole thing up ....

CAT

Fever DIY DIY天地 :: RE: DIY Marantz 7C

alfcat — Sat, 17 May 2008 05:02:14 GMT

發表人: alfcat
發表於: 2008-05-17 (星期六) 1:02 pm (GMT 8)

Dear alant,

I don't mind at all. I come here to learn and any advice is welcomed.

Yes, I am in that school. If your son happened to be in 1E, 3E, 5A, 6A or 7A, I am his teacher then. If your son is not is any of these classes, then your son is VERY LUCKY ... ha..ha.

CAT

Fever Activities 發燒活動/課程/團購 :: RE: 2008多項課程召集 - (3) 隔離牛製作班 (完滿結束)

wawawa — Sat, 17 May 2008 04:11:01 GMT

發表人: wawawa
主題: 音響隔離牛製作班
發表於: 2008-05-17 (星期六) 12:11 pm (GMT 8)

Dear Modi Sir,

我隻1500VA隔離牛有3個220V US插座,想將其中1個US插座改為110V,但隻牛只有1條藍色110V輸出線,請問如何接線法?

wawawa

Fever Activities 發燒活動/課程/團購 :: RE: 無鉛靚錫線團購

TonyWang — Fri, 16 May 2008 17:17:18 GMT

發表人: TonyWang
發表於: 2008-05-17 (星期六) 1:17 am (GMT 8)

請幫我訂一卷

Tony Wang

Fever DIY DIY天地 :: RE: 新做的CD機

biu40288 — Fri, 16 May 2008 16:40:38 GMT

發表人: biu40288
發表於: 2008-05-17 (星期六) 12:40 am (GMT 8)

AV AMP和電視之外,全是土炮
聲音方面我就各得比95係列還好小小

Fever DIY DIY天地 :: RE: 新做的CD機

accphoto — Fri, 16 May 2008 16:30:56 GMT

發表人: accphoto
發表於: 2008-05-17 (星期六) 12:30 am (GMT 8)

的聲如何？ Pass Lab X1 都係自已做的嗎？

Fever DIY DIY天地 :: 新做的CD機

biu40288 — Fri, 16 May 2008 16:00:56 GMT

發表人: biu40288
主題: 新做的CD機
發表於: 2008-05-17 (星期六) 12:00 am (GMT 8)

新做的CD機

Fever DIY DIY天地 :: RE: DIY Marantz 7C

alant — Fri, 16 May 2008 15:02:36 GMT

發表人: alant
發表於: 2008-05-16 (星期五) 11:02 pm (GMT 8)

Dear CAT sir,

Please don’t mind as I just add some remarks. (我只是過路一提，請不要介意) It is a basic electronics that: Under no loading condition, it is just an open circuit. The voltage measured is the input voltage. For this reason, you should mention the voltage measured with respect to no loading, half loading or full loading conditions, etc... Then, Accphoto may understand correctly.
In summary, there are two kinds of method to step down high DC voltage to low DC voltage:
1) Without using IC (not constant DC output):
=> The simplest method is use resistor. But, with different loading, the voltage drop in the resistor is different which causes variable DC output.
2) With using IC (constant DC output):
=> Using voltage regulator or IC (integrated circuit) and called DC to DC converter which exists both linear and switch mode. It can provide constant DC output. But, select low noise IC for audio device. There are thousand of topologies in DC-DC converter design. Just few references at
=> video lecture at http://www.youtube.com/watch?v=WMi-ZN3qtSs&feature=user
=> http://www.powerdesigners.com/InfoWeb/design_center/articles/DC-DC/converter.shtm
=> http://www.maxim-ic.com.cn/appnotes.cfm/appnote_number/2031/
=> http://en.wikipedia.org/wiki/DC_to_DC_converter
=> Photo as below. Today’s DC to DC converter is very compact, like a IC chip. Applications include notebook computer, mobile phone, ipod, etc... For Hi Fi audio device, I never try!

You may continue this topic with Accphoto as he is a practical guy in here. Lastly, may I ask you a question: Are your boss called “Brother Thomas Favier” after seeing your email address and your principal subject is Economics? He is school supervisor of my son. If yes, I know who you are.

B. regards,
alant

Fever DIY DIY天地 :: RE: DIY Marantz 7C

accphoto — Fri, 16 May 2008 13:55:01 GMT

發表人: accphoto
發表於: 2008-05-16 (星期五) 9:55 pm (GMT 8)

Yes, got to measure the voltage with loading, otherwise the voltage is not right. Besides, the resistor between b1 and b2 should be 4.7K, not 47K.

Fever Activities 發燒活動/課程/團購 :: RE: 2008多項課程召集 - (5) 膽後級組裝班 (公開接受報名)

modi — Fri, 16 May 2008 13:25:50 GMT

發表人: modi
發表於: 2008-05-16 (星期五) 9:25 pm (GMT 8)

大家好300B已進入測試了，很快大家可以試聽了。

Fever DIY DIY天地 :: RE: DIY Marantz 7C

alfcat — Fri, 16 May 2008 11:52:40 GMT

發表人: alfcat
發表於: 2008-05-16 (星期五) 7:52 pm (GMT 8)

Dear Accphoto,

Thanks for your help. I forgot to mention that the measurement was taken WITHOUT loading. If that is the case, should it be okay?

My Physics colleague told me that I may as well take a measurement with the loading as well. He said with loading, the voltage should drop significantly.

CAT

Fever DIY DIY天地 :: RE: DIY Marantz 7C

accphoto — Fri, 16 May 2008 05:03:06 GMT

發表人: accphoto
發表於: 2008-05-16 (星期五) 1:03 pm (GMT 8)

If input 310V AC, then output will be 310V x 1.4 = 430V DC and 309V DC seemed but the range that adjusted by the power broad should be more than 15V. There may be something wrong with the borad. Look for whether the diode position is correct or whether LM317 is working or not. By the way, did you measure the voltage with loading ?

Fever Activities 發燒活動/課程/團購 :: RE: 特別課程召集 - CDM-X CD 轉盤製作班 (只限CD理論/DAC課程學員)

Leon — Fri, 16 May 2008 04:44:51 GMT

發表人: Leon
發表於: 2008-05-16 (星期五) 12:44 pm (GMT 8)

I want Canare RCA socket. BTW, I don't have your mobile no. yet and so can't SMS you. Hope you can see this reply before leaving.

See you tomorrow.

Leon

Fever DIY DIY天地 :: RE: DIY Marantz 7C

alfcat — Fri, 16 May 2008 04:34:22 GMT

發表人: alfcat
發表於: 2008-05-16 (星期五) 12:34 pm (GMT 8)

Dear Accphoto,

The AC voltage from the Power Supply is 310V AC. After rectification, it becomes 309V DC.

I turned the adjustment knob (potentiometer?) on the Matisse board already. 309V DC is the MINIMUM I can get. If I turn it the other way round, it gives 325V DC.

Would you mind leaving your contact number at my email achan@sjc.edu.hk? There is something I still don't quite understand.... sorry.

CAT

Fever Activities 發燒活動/課程/團購 :: RE: 特別課程召集 - CDM-X CD 轉盤製作班 (只限CD理論/DAC課程學員)

kk_ho — Fri, 16 May 2008 04:23:47 GMT

發表人: kk_ho
發表於: 2008-05-16 (星期五) 12:23 pm (GMT 8)

AP and all,

Please let me know you need Canare RCA socket or Canare XLR socket.

SMS to me...............

Chicken Sir.

Fever DIY DIY天地 :: RE: DIY Marantz 7C

accphoto — Fri, 16 May 2008 03:58:54 GMT

發表人: accphoto
發表於: 2008-05-16 (星期五) 11:58 am (GMT 8)

You should direct wire from the power supply broad to B1 for left and right channel.
You should able to turn the Matisse Broad, what AC voltage you are inputing ? You can't use the 1M to reduce the voltage.

Fever DIY DIY天地 :: RE: DIY Marantz 7C

alfcat — Fri, 16 May 2008 02:52:43 GMT

發表人: alfcat
發表於: 2008-05-16 (星期五) 10:52 am (GMT 8)

Dear Accphoto,

I went there yesterday but I missed that part. Ah Tong Hing said I can use a 47K resistor to step down the 280V to 260V for B2+.

Yet, when I check the output from the Matisse Retifying Board, its DC out is 310V!! I think I need a 1M to step it down to 280V DC ....

Attached is the Schematics for the LITE M7 board. I "think" I have to direct a wire (underneath the board) from LEFT B1+ to RIGHT B1+ ... same for B2+ as well. Am I right?

Fever DIY DIY天地 :: RE: DIY Marantz 7C

accphoto — Thu, 15 May 2008 15:45:23 GMT

發表人: accphoto
發表於: 2008-05-15 (星期四) 11:45 pm (GMT 8)

I do not know the Lite Broad, why do you ask Master 棠？ He should know about the Board.