Playstation as CD-player

[NVD33]

Mick, the first 1002 PS I put my linear psu into only worked around 20% of the time.......

Hi,

I'm quite new on this thread but it seems that you face a power up problem. I have build a CD player based on CDPRO2 unit some years ago. This unit is powered with +5V (controls and DAC) and +9V (servos). If my memory is good, the specs say that at power ON the +5V must come first and the +9V after if not the CD is not working fine and sometimes the CD can spin backward! at power OFF the +9V must come down first. I guess that it's is the same for the PS1. Hope this will help.

Vincent

[Mick_F]

Vincent, thanks for your contribution.
I dont think that there is an issue with the order of the voltage supplies for the PS1. I believe so, because there are no circuits on the smps board that handle this. So the stock PS1 starts up supplying all voltages at a time.

A question to you as an owner of a CD2pro and a Ps1 based CD player: how do they compare soundwise?

Mick

[NVD33]

Hi Mick,

On my CDPro2 the circuit which output the reset signal at power ON is located on the display board! On PS1 the circuit which generate reset signal at power ON can be located elsewhere and not necessarily on smps board. My first power supply design for CDpro2 did not take into consideration Power Up sequence and I faced problem. May I suggest that people who face intermittent problem at power up with their linear power supply make a manual reset by using the reset button, if this solve their problem this mean that there is a power up sequence in the PS1. This is my suggestion but I am new to PS1 and Mick's opinion must be considered first.

About PS1 versus CDpro2 sound comparison please give me some listening sessions I will be back soon for that. Today I try to get rid of the TV set that must be connected to PS1 to navigate thru the menu!

Vincent

[Puffin]

I have had a frustrating morning. Finished my power supply and connected it to an unmodified 5552. Everything worked and listening from the A/V out it sounded pretty damn good.

However when I connected up to my modded 5552 it went through the initial turn on sequence and then just span the disc constantly. The pad controls would not work. I thought that perhaps the white wire needed some juice and gave it a couple of volts. No difference.

Went back to the un-modded 5552 and set it up again and it was fine,went away for 10 mins, came and the disc was spinning and the pad controls would not work !!!

I was constantly checking the DC levels and found that they were fluctuating quite a bit (down from 7.6 to 6.5 and 3.6 down to 2.6) could fluctuating current cause these problems ?

I made the boards from a kit that can take up to to 35 volts DC. the trim pot is 4K7. The fairly large heat sinks I have used get quite hot to touch.

Any ideas anyone ?

[Mick_F]

The idea of the regulator is that the voltage remains constant. So if it changes, as you have measured, something seems to be wrong.

Questions: Which regulator is used? Is there a serial resistor in the supply? For which max. current was your supply designed?

Mick

[Puffin]

Max current 1.5amps. I have got the thing working now and the joy pad malfunction seemed to be an urelated problem.

Since tweaking the voltage up a bit it seems to have stabilised. They use LM317's and yes I think there is a voltage resistor in series 120ohms.

[pieroh]

Hi Puffin,
my PS behaves in the same way. Sometimes I have to reconnect the powersuppply several times to get it to work!

Does your PS play a whole CD without skipping? I have the feeling that this phenomena is not a problem of the PSU but one of the laser unit settings.

pieroh

[Puffin]

Pieroh. You could be right. I have now had it running for some hours and it is behaving impeccably !, but tommorrow is another day !

I have also found that the modified PS1 sounds better as a result of the mods than the unmodified, probably as a result of the limitations in the original power supply. The only PS1 (I have 3) that the new power supply will work with is unmodified. However using the A/V out, and linear PS it sounds as good, if not better than the modified with SMPS power supply ?!

[willbewill]

I've had this same problem with unmodified PS1, but once drive unit was swapped out for a 9002 unit problem disappeared.

[AnthonyPT]

Hi

I was looking at the diagram for the
psu connections and see that according
to this pin 5 is always connected once
the power supply is plugged into the mains.
So if when making a new PSU for the 1002
would you say having a delay solenoid that
switches the other lines on once the new
custom mains switch for the LM317 based
PSU is activated? On the standard PSU
is Pin 5 always alive when the cord is
in the back of the player?

regards

AnthonyPT