Hi @all,
again the question i posted before.
I have a question about the Gain and Bias adjust some of you've done. I've adjusted about 5 PS1 with different laserunits and if i take the value of Bias 1,7 V and Gain 1,85 Volt most of the CD don't started. My values with all laserunits are : Bias 1,54 V and Gain 1,75 V. I wonder why with Mick values my PS don't read all CD `s.
Any experiences ?
Dommi
again the question i posted before.
I have a question about the Gain and Bias adjust some of you've done. I've adjusted about 5 PS1 with different laserunits and if i take the value of Bias 1,7 V and Gain 1,85 Volt most of the CD don't started. My values with all laserunits are : Bias 1,54 V and Gain 1,75 V. I wonder why with Mick values my PS don't read all CD `s.
Any experiences ?
Dommi
Dommi said:
Sorry for my late answer. I didnt notice that the thread was going on .....
Good question. I have those values from a site for PS1 players. It works fine with most of my CDs, and I have used to for adjusting all of my PS1s up to now. Maybe your values are even better...?!? I will try it on occasion.
Mick
Dommi said:
I confess that I built these in before I heard of backs finding that the PS1 draws such high currents. I bought them at an ordinary local electronics store and I have no idea about their current rating. They may well be underrated...
I must say that I am still not absolutely convinced that the PS1 draws currents as high as 5 amperes, and I resolve to make a measurement myself.
Mick
Mick_F said:
hey mick i didn`t measure ps1`s current draw i just made
the first psu with lm3172AMPS and it couldn`t start.
then i added the 2n 3055 and it works ok.
the original psu`s rectifiers are rated 6 AMPS.
my guess is it`s somewhere between 3.5-4.5 AMPS and most of it
goes to the transports motor.
Ok, here is the latest research report from the workshop:
I have measured the currents from the PSU to the Mainboard.
Pin 1 (7.6 V): 0.3 - 0.5 mA when running, 0.2 mA when stopped. Peak current when the motor starts is about 0.6 mA.
Pin 3 (3.6 V): 0.5 mA when running and when stopped.
Pin 5 (3.6 V): Could not measure any current.
Back, I am sure that the currents are not higher. I have measured with my DMM set in the mV range and the fuse did not blow. Btw, that of course is also a means to test the upper limit of the current. Just connect the PSU through a low-amp fuse and see if it blows.
Maybe something else was wrong with your first PSU approach....
I have also measured the Voltage on the solder blob on the flat cable to the laser unit. I found 12.7 mV. I guess the cable I use is the short one, so I may lower it a little bit.
Mick
I have measured the currents from the PSU to the Mainboard.
Pin 1 (7.6 V): 0.3 - 0.5 mA when running, 0.2 mA when stopped. Peak current when the motor starts is about 0.6 mA.
Pin 3 (3.6 V): 0.5 mA when running and when stopped.
Pin 5 (3.6 V): Could not measure any current.
Back, I am sure that the currents are not higher. I have measured with my DMM set in the mV range and the fuse did not blow. Btw, that of course is also a means to test the upper limit of the current. Just connect the PSU through a low-amp fuse and see if it blows.
Maybe something else was wrong with your first PSU approach....
I have also measured the Voltage on the solder blob on the flat cable to the laser unit. I found 12.7 mV. I guess the cable I use is the short one, so I may lower it a little bit.
Mick