Hi,

the stereo decoder could be adjusted without a 2-Channel Oscilloscope! There are 2 ways described in the manual: Stepp 11-13  or  14 and 15. The step 14 uses the oscilloscope in the X-Y Mode, this is not a 2 Channel mode instead it uses the normal y -input  and the horizontal deflection is controlled by the x-input signal and not via the timebase.

The resistor is the (backup) supply for the transistor if the lamp is broken or disconnected it still gets the supply voltage so that the stereo decoder doesn't supress the audio signal.

For the scale pointer ask memeber 'Dillen' he might have one for you.

Danke für die schnelle Antwort!

Da ich ja über ein gutes Antennensignal verfüge, auch die Empfangsqualität des Beomaster 1001 ist gut,

(Mein Beomaster 3000 erkennt übrigens problemlos FM stereo mit dem gleichen Antennensignal)

gehe ich entweder von einem defekten Transistor oder einem total dejustierten 19khz Kreis aus.

Ich muss nicht unbedingt alle Justagen durchführen? Reicht es aus die Justagen 13 und14 zu machen?

Dann werde ich normal ein Oszilloskop ausleihen und der Sache etwas tiefer auf den Grund zu gehen.

Wie erreiche ich Dillen, einfach über eine PM oder per email?

Martin, dessen Username Dillen lautet, kann mittels PM erreicht werden. Oder über seine Webseite:

Hallo,
nachdem ich den Beomaster 1001 seit Januar erst einmal wieder ins Regal gestellt habe, habe ich jetzt mal wieder Zeit mich dem STEREO -Anzeigeproblem zu widmen.

Ich messe mit dem Oszillosop das 19 kHz Signal an punkt A und kann ebenfalls an Punkt B messen.
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An den Punkten C und D bekomme ich kein Signal angezeigt !

Die Transistoren TR 14 , TR15 und TR16 sind ok auch die angegebenen Spannungen werden an den Transistoren gemessen.
Die Kanaltrennung des linken und rechrte Kanals funktioniert und an den Transistoren TR17 und 18 wird ein NF Signal abgegeben!
Wer kann meinen Gedanken einen Denkanstoß geben wo ich nach dem Fehler suchen soll?

Ich habe keine Ahnung, was TR46 bewirkt!

Ganz nebenbei bemerkt, die Stereo Birne ist OK !

here in English for the foreign forum members:
Hello,
After putting the Beomaster 1001 back on the shelf since January, I now have time to devote myself to the STEREO display problem.

I measure with the oscilloscope the 19 kHz signal at point A and can also measure at point B.

At the points C and D I get no signal!
The transistors TR 14, TR15 and TR16 are ok and the specified voltages are measured at the transistors.
The channel separation of the left and right channel works and at the transistors TR17 and 18 an NF signal is output!
Who can give my thoughts a food for thought where to look for the mistake?

I have no idea what causes TR46!

By the way, the STEREO lamp is OK!

the Beomaster 1001 does not turn on the STEREO lamp when switching to PHONO or TAPE as the Beomaster 1200 does!
Is there a technical service message from B & O?
or does someone have a hint how to change that?

Can you tell, if the Beomaster actually plays stereo?
Try listening for the sound picture and switch to mono and  back.

If the voltage on the collector of TR16 is less than 1V as stated in the schematics, then either the connection
to the lamp, the 680 Ohm resistor, the positive supply voltage to the lamp, or the the lamp itself is bad.
Alternatively the tuned circuit at the collector (coils 8012052) is greatly off tuning or broken.

Martin

hello Martin, thanks for the tips.

No, I can't say that is FM stereo is what I hear, the difference between the channels is too small, when i switch MONO oft/on.

The stereo lamp itself is OK, if I ground the collector of TR16 briefly it burns!

I can only check your other tips tomorrow.

I once thought, what TR46 has a t do, can it be that makes a kind of noise reduction, if no station is set?

He gets his signal in the ZF circle!

Best regards 

TR46 was introduced in production. I cannot tell you exactly why, but it seems
to be able to set the amplification of TR14 based on the signal level at the IF stages.

Martin

by a "slip-off" with the measuring tip I have the TR16 shot down.

Now I measure 32.5 V at the collector.

Unfortunately I have no replacement for demn BC119 at hand and must first wait for the delivery.

I will keep you informed