[Dillen]

OK,
Here the march (attached).
No singing.

Martin

[Dillen]

There’s a march too.
Do you want them?

Martin

[Dillen]

Katy Bødtger with Deccas Dance Orchestra – B&O Stereomelodien (vals).
(Attached file).

Martin

[Dillen]

None that I am aware of.
You must take out the drive and rotate the flywheels by hand – or using some kind of suitable tool to carefully push them round.

Martin

[Dillen]

Good job!

Martin

[Dillen]

A bit difficult, and it really depends on which version of drive is fitted in your Beocord.
But basically it’s a matter of rotating the flywheels by hand (Beocord unpowered) until
the tapehead bridge disengages.
Note that the two flywheels rotate in opposite directions; Left one clockwise, right one counter clockwise as seen from above.

-And replace belts.
Correct belts here.

Martin

[Dillen]

Has C7 (220uF) shorted?

Martin

[Dillen]

During playback , do you have signal on pin 4 on both Dolby ICs?
What is the DC voltage on pin 5 (Vref) and pin 28?

Martin

[Dillen]

Which version of Beocord 9000 do you have –  serialnumber?

Martin

[Dillen]

Will the Beocord play back tapes recorded on other decks/factory recorded tapes?
Does tapes recorded on the Beocord play back correctly on another deck?

Martin

[Dillen]

Can we see a photo of your Beogram with the platter height visible?

Martin

[Dillen]

A very low platter/subchassis setting can often cause wow.
Reason: A 12″ record is a larger diameter than the platter and the wow comes when the record touches the
surrounding surface – gradually increasing as the tonearm and carriage move inwards, shifting the subchassis’ center of gravity.
First tracks play fine, later tracks not.
The solution is to tighten up the suspension a little at the left/rear.

Don’t overdo.
Make sure the subchassis is still able to move freely.

Martin

[Dillen]

From same territories, generally, yes.
Refer to the part numbers in the service manual and the 4-digit type numbers found on the serial number labels to make sure.

Martin

[Dillen]

Is the amplifier sections powered at all?
Bad relay?
Blown fuse?
Cracked solder joints where leads go to the relay board?
Open ceramic resistor on the relay board?

Martin

[Dillen]

No! It’s made like this and it’ll work fine.
(Actually the best and most stabile operating temperature for many semiconductors of this sort is 60-70 degC).

Set the idle current as adviced in the service manual.
Final adjustments are done with the Beomaster under normal working conditions (warm).

If the idle runs astray (keeps increasing, also after a few minutes) there is a problem
somewhere, – most likely lack of thermal coupling from the output stage darlingtons – or from the temp. sensing transistor in the constant current generator – to the cooling fins.

(Never run an amplifier like this without the cooling fins – it’ll do a thermal runaway).

Martin

[Dillen]

The rush-in current at power up is quite substantial. Not all voltage converters like that.

A dead prescaler usually won’t affect the function of the tuner. It would merely mess up the displayed frequency.
Check the cables to the tuner boards, at least the screened one that goes to the CPU board
is easily pulled off inadvertently.
Check also the solder joints at the two tuner boards interconnecting plugs.

Martin

[Dillen]

Keep in mind that the record is typically thicker around the perimeter than in the actual playing area,
– to ensure the needle moves inwards in order to find the groove – rather than outwards.

Martin

[Dillen]

No, these are not ICs you would enjoy replacing just for the fun of it.
Put a scope on the control pins and see if everything goes to binary plan when you run the volume up and down.
If it does, swap the two ICs to see if the problem moves to the other side.
If it doesn’t, find out where the missing bit went missing, bad connectors, cracked solder joint, broken cable etc.

Martin

[Dillen]

Missing bit to one of the volume control ICs.
Or a bad IC.

Martin

[Dillen]

There are several, slightly different, versions.
Three of the ones shown here have different transistors, and the last one is an entirely different (earlier) version, mainly seen in 41FV and 42FV.

Martin

[Author]

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