Philips CD104 tweaks

[Elso Kwak]

Originally posted by poynton


Hi.

The only way to repair this problem is to drill out each griplet and solder a wire through from top to bottom.

Resoldering will not cure the problem!!

Andy

A college of mine, when I was repair-tech, who did many Philips CDPs as his shop sold them a lot, told me resoldering was adequate.

[Bernhard]

I have a few tested servo boards to fit into CD104, 204, 304, 304mkII, Grundig CD7550, and maybe others.
This fixes 99% of all problems.
15 € incl. registered shipping inside Europe, 20 € rest of the World.

[poynton]

Originally posted by Elso Kwak


A college of mine, when I was repair-tech, who did many Philips CDPs as his shop sold them a lot, told me resoldering was adequate.

Hi.

Resoldering would be adequate IF the plate-through was always 100%. Wiring through the hole makes sure!

Andy

[Elso Kwak]

Originally posted by poynton


Hi.

Resoldering would be adequate IF the plate-through was always 100%. Wiring through the hole makes sure!

Andy

As far as I know the wire is already through the hole

[Gasho]

How many problematic joints are there on servo board ?

I found two or three , and others are allready factory wired.

Audio board has no such joints , all looks like wired ones , like shortcuts from trace side (two of sloder joints) to ground side.

[jives11]

Originally posted by Gasho
How many problematic joints are there on servo board ?

I found two or three , and others are allready factory wired.

Audio board has no such joints , all looks like wired ones , like shortcuts from trace side (two of sloder joints) to ground side.

thats right, there are only two griplet holes in the servoc board plus a number of wire links and axial caps with large solder 'blobs' at the end. The links and caps I resoldered (sucked the old solder and resoldered) the 2 griplets I desoldered untill I could see the end of the griplet. I drilled a hole through the middle of the griplet, desoldered again, then ran a small lenth of tinned wire through the hole and resoldered on either side. NOTE The griplet is still there, I found them too hard to remove without removing the tracks on the non-copper side.

The audio (decoder) has approx 10 griplet connections through plus a couple of the cap/wire link blobs.

[Gasho]

Still no TOC and music from my player.

I run tests with oscilloscope but didn´t see any errors.

Signal goes from transport to DAC board and to decoder board.

I don,t know how looks a good signal but it is present so that indicate that laser pick up is reading something from CD when I press play button.

I will run some tests again.

Maybe the quartz that feeds microcontroler is running out from correct frequency , maybe spindle motor don´t have correct speed.....

Any sugestions?

I have service manuar of CD104 but there is a lot of difference from 304 mk2.

Must check all solder and ground points again .

[jives11]

looking at the decoder schematic, I notice that some of the wire links distribute power to various chips. I wonder if these links could be better replaced with ferrites or small value inductors ? I'm guessing that the supplies are modulated by the clock freq so does anybody

1) Believe this is a good idea

2) suggest a value of inductor/ferrite suitable to attenuate noise in the 4Mhz region

[poynton]

Originally posted by jives11
looking at the decoder schematic, I notice that some of the wire links distribute power to various chips. I wonder if these links could be better replaced with ferrites or small value inductors ? I'm guessing that the supplies are modulated by the clock freq so does anybody

1) Believe this is a good idea

2) suggest a value of inductor/ferrite suitable to attenuate noise in the 4Mhz region

Hi,

Taking your 3 jumpers from the top.

1. The one next to diode 6561 is connected to a 47uH choke 5505 before reaching the ram.

2. This could be replaced by a choke - all the rest are 47uH. Decoupling on this chip is done by sm cap 2538 - the tracks for this are rather long. I would add a further cap soldered to the ic pins.

3, The last link is also decoupled 'remotely'. I think an extra 47uH or bead plus extra decoupling cap closer to the ic would not go amiss.

Andy

[jives11]

Originally posted by poynton



Hi,

Taking your 3 jumpers from the top.

1. The one next to diode 6561 is connected to a 47uH choke 5505 before reaching the ram.

2. This could be replaced by a choke - all the rest are 47uH. Decoupling on this chip is done by sm cap 2538 - the tracks for this are rather long. I would add a further cap soldered to the ic pins.

3, The last link is also decoupled 'remotely'. I think an extra 47uH or bead plus extra decoupling cap closer to the ic would not go amiss.

Andy

Thanks Andy, any thoughts on the fourth link

I also noticed that the Right channel has no local ceramic on the +12v supply. The left Channel does and the -12v does. The +12v gets delivered all over the baord as well as the NE5532's. This supply is decoupled by 2627 (22uF). I use a starget here of 47uF but wonder if an alternative cap would be better given the dual role of supplying both analogue and digital supplies.