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This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022

 

Beogram CD-X Restoration

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Menahem Yachad
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Jerusalem, Israel
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Welcome back, Menahem!

I haven't done any B&O in a while.

A lot of TV repairs, but here I have a butchered CD-X for restoration, not working.

Cheap Chinese caps, one soldered in the wrong polarity, wrong capacitance values, sellotape insulation on wires, bloodstains everywhere (I've washed all the PCB's).

Going well - I have recapped the PCB's, resoldered all the PCB joints, and put wires in all the griplets.

 

On the PSU block, there is a light blue 0.047uF ceramic capacitor grounded to the 7812 regulator heatsink - the other end, I have no idea.

Does anyone know where this connects?

Dillen
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Dillen replied on Thu, Jan 4 2018 12:02 PM

It sits "flying across in open space" with the other end connected to the analogue board.

Martin

Menahem Yachad
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By analogue, do I presume correctly that you mean the Decoding PCB, with the 2 NE5532 op-amps?

Connected exactly at which point on the underside of the Decoding PCB?

It's obviously a decoupling cap.

sonavor
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sonavor replied on Thu, Jan 4 2018 4:25 PM

Hi Menahem,

I found an old picture in my archives that show the capacitor in question.


John

Menahem Yachad
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John

Thank you so much!

That is the decoupling for the audio ground signal.

Menahem Yachad
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Project complete.

Calibration as shown 1V p-p, and 540mV Laser Current.

A real *** to connect to the test points with the machine assembled!

 

It plays pre-recorded discs excellently, but skips on home-burned CD's.

I'm just wondering whether this is normal - when this was released, there was no such thing as a CD-Writer yet.

chartz
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chartz replied on Tue, Jan 9 2018 7:39 AM

My CDX and other CD104 based payers all read home-burned CDs perfectly Menahem. No problem at all. Even the older Sony CDP-101 and Philips CD 100 do.

Jacques

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