Arcam Alpha 5 CD - playback problem

This is my first post here so Hi to Everyone

Recently I've bought Arcam Alpha 5 but unfortunately some problems appeared soon after :(

It reads TOC every time but playback is delayed. Well sometimes it's OK but other time you have to wait few minutes until it plays. No matters what CD, CD-r, scratched or not. There is playback icon on display but no activity on laser head. Once it can be all day OK while other day you have to wait long every time CD is inserted :mad:

Other thing that I've noticed is that when I'm pressing the load button, laser doesn't wait until drawer pull back but it's "checking" immediately is there a CD while it's not yet in the position and it's displaying "no disc". When I'm pushing the drawer by finger it's OK

I've replaced CDM-9 laser pickup but it didn't help. I haven't found any cold joints or leaking caps :confused:

After few simple mods player plays very nice so I'm desperate to restore it to full health.

Any advices and ideas are welcome :)

Best Regards
Kamil
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
Not familiar with the playe,r but the player thinking there is a disc present when there isn't points to a possible problem with the drawer/tray microswitches that tell the system control what state the player is in.
 

szawszaq

Member
2010-10-28 9:41 pm
Cork
Hi Mooly
After your suggestion I've checked the micro switch - it's very simple and it works fine so problem is somewhere else.

I'm suspecting one of the microprocessors that is processing signal from the switch and laser but I have no idea which one could it be and how to check it if find it.
 

Mooly

Administrator
Paid Member
2007-09-15 8:14 am
It's never the microprocessor as a general rule... I say that from years of experience as a service tech.

The next step is to locate a manual and to go around every pin on the system control and uprocessor with both a DVM and a scope and make sure everything is what you would expect. That includes grounds and supplies too.
You have to be logical...
 
Thanks Mooly, what you're saying has sens so I will follow that.
I've already mailed arcam requesting pcb schematics so it looks like I will have to do my homework from theoretical and practical electronics.

But in the first place I will replace rest of capacitors that I haven't replace before.