Hi Per,

Thanks for the new screen shots. 
Your voltage level readings look a little high.  Make sure the scope probe setting (1X or 10X) matches what the corresponding level is on the oscilloscope setting for the probe channel.  They should both be set the same (either both 1X or both 10X).  That will give you a correct voltage reading on the scope.

From what you show though...I believe they confirm that when you press On that the forward motor command is there but then it goes away as a control signal in the Beogram is sending a command to reverse.

My workbench is pretty full up right now but I will try to sneak my Beogram 4000 and show the same measurements to compare to.

Regarding the counter weight, it is out of adjustment.
Did you perform the balance with a cartridge mounted?  If not, you need to.
Try it again with the cartridge mounted.

-sonavor

Hi sonavor,

I saw now that the probe for Ch2 had accitently slided from 10x to 1x (the scope is still set to 10x). Do you want me to measure again?

Regarding the tonearm balance:

"Were you making the zero balance adjustment with the tracking force knob set to zero?" -Yes, I did.
"Were you making the zero balance adjustment with a phono cartridge attached?" -Yes, and without the protection.

Per

Hi Per,

No need to remeasure the voltages again just yet. Wait until I measure and post mine.

On the tonearm then...it appears the calibration is out of adjustment.
One thing to keep in mind is that there are physical limits to the range that the counter weight can be placed.
Obviously the Beogram originally came from the factory perfectly adjusted so the position you have it at is not correct.

Back it off so the Beogram tonearm can operate correctly.
To re-balance it you will have to do some recalibrating of the tracking force knob. 
It uses a spring to increase/decrease the force as the knob is turned.
There is a tiny set screw at the top of the knob assembly that locks its position.
Loosen that screw so you can reset the starting position of the tracking force knob.
Without any force on the knob you should be able to adjust the counter weight to a good position.
After that you can readjust the tracking force knob to where it indicates the force correctly.
I do that by holding the amount of force dialed in with one hand and putting on the dial knob with the other...then tightening the set screw and measure the resulting force. Be extremely careful to not over torque the screw (any screw for that matter).

It can take several iterations of adjusting everything to obtain a good result. Quite tedious sometimes.
For that reason I typically try adjusting for a tracking force of 1 gram during this procedure rather than zero. That is because I normally use 1 gram to 1.2 grams for my tracking force setting.

I hope that helps.

-sonavor

Hi sonavor,

OK, thanks. Then I'll await your measurements.

Regarding the tonearm, are there any pictures online for this adjustment? I can not recall I've seen it on Beolover.

Per

Yeah, I don't believe we have shown that procedure on the Beolover Blog before. Probably because it requires both hands and is so tedious. It also isn't a procedure that you should commonly have to do. Sometimes though, as in your case, the mechanics seem to have gotten too far out of adjustment.

Here is a photo I made a while back that shows all of the components relative to the tonearm balancing.

Normally the tracking force knob setting is fine and the counter weight is only slightly out of adjustment.
As I noted before, there is limited room for adjustment of the counter weight.
Too close in and the tonearm cannot pivot up an down.
Too far out and bracket that connects to the arm lowering lever will not work correctly.

With the tracking force knob removed as shown in the photo there should be no force at all since the spring loaded gear that applies the force is unloaded.
You can start at that point and zero balance the arm. That should result in a good setting of the counter weight.
Then you can attach the adjustment knob, set it to 1 gram and see what you read.
That is where you can get into a few iterations of setting the position of the knob. 
If you cannot get 1 gram set with the adjustment knob then you will have to make a small movement of the counter weight.

Hi Per,

I connected up the Beogram 4000 turntable I have in my workshop to an oscilloscope and took some measurements of key signals involved with the servo motor. I looked at six signals:  FF, /Q0, FR, /Q2, the forward servo motor node and the reverse servo motor node.

My oscilloscope can measure four signals at a time so I divided my measurements up.
I exercised the Beogram while looking at the four control signals (FF, /Q0, FR, /Q2) and while looking at the motor nodes plus two control signals (/Q0, /Q2).

Here is my test setup.
I opened the Beogram and removed the platter.
Then I soldered on some test leads to the six nodes I wanted to measure. I connected a clip from the probe grounds to the Beogram gound.

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Now to look at the measurements.

-sonavor

The first Beogram 4000 servo signal measurement is of the "ON" event.

Here are the four control signals during "ON"

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Here is the "ON" event showing what is going on with the servo motor nodes

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Here are the motor signals for the "OFF" event

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Next I will show the fast and slow scanning events.

On the Beogram 4000 servo motor during forward/reverse scanning here are what the control signals are doing.

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Here are the servo motor nodes during tonearm scanning.

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Hi Per,

Those Beogram 4000 waveform measurements for the servo motor are from a properly working Beogram.

From what you have described on your BG4000 and shown from your oscilloscope, I believe your issue is still what a control signal.
You always get a reverse servo motor command.  Even when you manually advance your tonearm, then plug the Beogram in (if I remember correctly).

On my BG4000, I can advance the tonearm out to the middle of a record, unplug the Beogram...When I plug the Beogram back in it remains off until I press "ON" again.

If we assume that your Beogram 4000 was working perfectly when you bought it then the current problems are due to the shipping damage. Something is out of place related to the BG4000 servo commands.

Otherwise we decide that this Beogram 4000 was faulty to begin with and the problem could be something electrical internally that has to be found and fixed.

The first scenario seems more likely.

My suggestion is to connect the scope to control signals and verify what state they are in for the "ON" event.
I will leave my Beogram 4000 and with the test wires soldered on in case we need to compare some other signals.

-sonavor