whining kss210A after replacement

[jitter]

I used to work in a calibration lab for industrial and lab type instruments.

Ah, then you're one of the guys we send our equipment to once a year to have it checked and calibrated (an ISO requirement).

While calibrating using BNC connectors, you are terminated properly. This preserves the bandwidth. Notice that BNC stuff normally terminates with a 50 ohm load.

You're absolutely right. But I always have to be careful to check my cables, as we have 75 Ohm types as well (we make a lot of stuff for the broadcasting industry too). But a quick check of the thickness of the insulator in the BNC plug is al that's needed.

I was referring to your last screen shot, probably around 0.5mS / div. I set up that way often to set up E-F balance. Triggering is a pain to get right. Try that with a DSO (I have, it seems to be more difficult to get a good display). Your focus is not the issue. I'll have to find a shot of this, or we'll have to wait for the next CD player I do.

DSOs usually are nice things to use but they can have some major drawbacks. E.g. getting a nice XY trace on the screen of certain products I test is simply impossible with a DSO. A € 300 analogue scope can sometimes do things a € 10.000 DSO can't (properly)...

The 2nd picture is 0.2 ms/div setting, channel inverted. I'd like to see your shot, because if I can still improve the adjustment of the CD-4, then I'll do it...

 

[anatech]

Hi jitter,

Ah, then you're one of the guys we send our equipment to once a year to have it checked and calibrated (an ISO requirement).

Yes. That was my job, and I was certified to create limit test sheets for all 13 labs. A few people in each lab was supposed to be certified for this. I quit that job some years ago. Liked the hours, didn't like the pressure to do a quick job that was not in tolerance. We had to put our name on our certifications.

One warning. Always get your certificates with full data, all as found and as left data points. Otherwise, your certification may be a joke.

But a quick check of the thickness of the insulator in the BNC plug is al that's needed.

I always read it. Some 75 R cable can be very thin.

DSOs usually are nice things to use but they can have some major drawbacks.

Yes. The best two I tested recently were the Agilent 6000 series and a LeCroy Waverunner (nice 'scope too).

I'd like to see your shot, because if I can still improve the adjustment of the CD-4, then I'll do it...

No problem. I can't find my shots, so I may need to do this again with another CD player.

-Chris

 

[jitter]

Hi anatech,

Hi jitter,
One warning. Always get your certificates with full data, all as found and as left data points. Otherwise, your certification may be a joke.

Luckily it's a job of a colleague to do that. I say luckily because when it's time to send another batch to be calibrated he's the one who has to collect the items and deal with people unwilling to part with "their" test-equipment. 😉

I always read it. Some 75 R cable can be very thin.

I know, but I was not referring to the cable. 50 Ohm BNC plugs have thicker dielectric than 75 Ohm plugs.

Yes. The best two I tested recently were the Agilent 6000 series and a LeCroy Waverunner (nice 'scope too).

The technician who deals with the broadcasting equipment uses the Infinium 8000 to trace errors. That stuff is all digital and HD now so a 1 Ghz scope is no luxury. The R&D department mainly uses LeCroy.
I often use an older hybrid (analogue/DSO) Fluke scope.

We're getting a little off-topic, though, so back on-topic:

No problem. I can't find my shots, so I may need to do this again with another CD player.

Thanx!

 

[jitter]

I remembered wrong, the broadcasting guy uses an Infiniium 5000 series, which is a 4 GHz (20 GS/s) scope.

But willos we haven't heard from you for while, have you had any succes?

 

[willos]

Hi Jitter, Mooly and Chris,

I have been reafing your knowledge exchanges but had nothing to report... yet. Yesterday I tweaked the OF pot a bit more and the player behaves well since... Maybe I did not need a new laser after all???

It's a bit premature to cheer aloud yet, but I'll keep my fingers crossed and will get back to you next weekend.

Greetings and thanks,
Willem

 

[anatech]

Hi Willem,
There is a laser current test point where you measure the voltage across a resistor. You are allowed 10% over the value printed on the laser head itself. Poor RF signal or servo faults are other forms of head failure.

Normally, the disc (or spindle) motor is the cause of trouble. The exact table height is critical if you attempt to change it yourself. You need to be within 0.5 mm (per many manuals), 1 mm on the outside. The closer you are, the better the machine will work.

So, yes. The original head may be fine. Kinda hard to see from here! 😉

-Chris

 

[Mooly]

Keep us informed 🙂

 

[willos]

Gentlemen!

I played a lot of (critical) CDs the last few days and the 1420 has been performing flawlessly. So I think this topic can be closed as far as I'm concerned.
I am very grateful for all your help; I learned a lot and think I know what to do when a pickup decides to really let me down in future.

Thank you very very much!
Best regards.
Willem

 

[Mooly]

That's really good to hear 🙂

Karl

 

[anatech]

Hi Willem,
Cool. Glad to hear this.

You should have a look at the different signals so you know what to expect. Take pictures with a digital camera and you can refer back to them later.

-Chris

 

[willos]

Hi Chris,

Another useful tip!

Thanks,
Willem