[Dillen]

“A lamp 12v/80mA has the same characteristics even bought from beoparts or elsewhere.”

True.

But quality could be the difference.
From Asia you can often buy very cheap lamps meant for use in plastic toys.
They typically have a rated lifespan of, perhaps, 200 hours (and tolerances not worth mentioning).
You will often find these listed on Ebay and similar places for next to nothing.
If you go for this quality it would be a good idea, as suggested in the linked thread, to buy
lots of ten or more and, if you use your Beomaster on a regular basis, you will also
develop good lamp replacement skills.

Lamps from Beoparts-shop often have an expected lifespan of 2000 hours, some even 5-8000 hours.
Some lamps sold there are actually custom produced.

And the resistor will run warm.
That’s Ohms law.

Martin

[Dillen]

Check for cracked solder joints, particularly where connectors and the piggy-back boards are soldered in.
Does it run warm on the cooling fins? If so check the idle current settings.

Martin

[Dillen]

That’s a homemade solution.
The spring plate is not supposed to sit under the keyboard like that.

Martin

[Dillen]

The recitifier board pulls right up when you pry away the small black claw that holds it.
The regulator itself has three pins that goes into a connector. The regulator stays with the chassis.

The filter capacitor is a “soldering star” type – not a snap-in. They are known to go bad.

Also check the rectifier diodes. I’ve seen cases where owners fitted schottky types, – not sure why, presumably in a misunderstood attempt at improving something,
– and they are no good in this position. They typically go with a bang.

Martin

[Dillen]

You can find test/calibration/alignment records in good shops, on Ebay or f.e. here:
https://www.discogs.com/search?q=stereo+test%20record&type=all

Note, that test records should not be bought “used” unless you trust the seller.
If a test record was played using a bad needle, it could be damaged and absolutely worthless.

Martin

[Dillen]

matador wrote:

Our beograms do not have (unless I’m mistaken) a lot of (if any) adjustments beside tracking force. No azimuth, no anti skating, no “whatever it is named I don’t even know what it is”…

Eh, what?
Which model Beogram are you talking about?
The term azimuth is mainly used with tapedecks, but the angle of the cartridge (rotation and/or parallelism) can be adjusted in many Beogram models.
So can anti-skating, even if a knob or dial for this is not in direct view.

Test records are good for countless things.
Many of the following parameters and properties can be checked using
one or more test records, – and most can be adjusted or manipulated in some way;
Tonearm height, tonearm parallelism, tonearm rotation, (& tonearm length for tangential models), tracking angle, tracking force, anti-skating, platter speed, wow, flutter, rumble.
Also general stylus condition, channel separation, distortion, frequency response (stylus and RIAA) etc. can be checked using test records.

Martin

[Dillen]

Originally, a special tool was available in order to align the spindles position.
This tool is nowhere to be found, so in most cases a careful check for free spinning of the spindle is all we can do to get it right.
The coil block and the two plates holding the bearings can be moved in relation to each other.
It’s not a lot, actually very little, but even an ever so tiny move could result in a much more free rotating spindle. As can a little wiggling of the spindle to make bearings run “clean” on their inside races axially rather than rub on edges.
Rotate the spindle by hand, and watch the run down time. The spindle should run for as many seconds as possible.

The motor will normally run a little warm after some minutes, but not hot.
If it runs hot there is something run. Has its coils been correctly electrically connected (in series and not parallel etc.)?

Martin

[Dillen]

Sure you have the spindle aligned correctly axially with the bearings?
Does the speed adjustment move the small magnets all the way out and away from the brake disc?

I take it this is not a 60Hz (US) deck running on 50Hz (europe etc.)?

Martin

[Dillen]

Correct belt?
Check if the belt rubs on something.

Martin

[Dillen]

Does it lift slow?
If so – dry or wrong lubricants?

Has it worked while in your possesion?
If not – wrong cam wheel for this model, perhaps?

Martin

[Dillen]

Did you check it with a proper gauge?
If you don’t know who set up the Beogram and how, you shouldn’t trust the dial.

Martin

[Dillen]

Nothing wrong with that pin. It’s free and fine.
And the typical symptom of a locked pin is that the tonearm doesn’t lift anymore, or only lifts very slowly.

What cartridge is fitted, and have you checked the tracing force?

Martin

[Dillen]

What are all those white wires on the main PCB?

And where does that module with the SMD caps come from?
From the trademark logo I assume it must be a genuine Bang & Olufsen board, but I don’t recognize it.

Martin

[Dillen]

If the contacts plating has gone, the connector is pretty much worthless.
Looks like the connector on the tonecontrol module – right?
Is it “only” the male part that has lost its plating or also the female part on the “piggy-back” PCB?

Martin

[Dillen]

The buttons are stuck in dry lubricants.
Pull the knobs off, clean both sides of the metal blade for each knob and the respective
mating slot in the knobs plastic backside.
Contact cleaner can often help dissolve and shift the dried stuff.
Sometimes IPA is better. Try and see.
Pipe cleaners are good for cleaning both parts as they can be shaped to suit and will fit nicely in the slot.
When clean add a little silicone grease (of the non-hardening type) to the slot in the
plastic backsides and push back the knobs.

All this can be done from the front.
If a knob is really stubborn, you can lever it off careful using a flat-bladed screwdriver
from below into the knobs recess and against the front frame with pieces of thin cardboard between to avoid scratching.

Martin

[Dillen]

matador wrote:

Maybe there?

– Which actually mentions Beogram 4000 as well.

Martin

[Dillen]

ummagumma wrote:

Soundsmith in the USA make hi quality B&O replacement stylus https://www.sound-smith.com/bo-cartridges

For the SP cartridges discussed here, they only offer a rebuild service.
It would be much cheaper to find a good quality stylus on f.e. Ebay and replace it yourself.
For the Beogram 1200 it must be a 15deg tip, like SP6/7/10/12/14 – no SP1/2.

Martin

[Dillen]

ummagumma wrote:

I have the service manual, but many sections are illegible due to shadows/focus problems from whoever scanned the doc. Pgs 2-5, 4-1,7-2, 10-1, 10-2, and the last page diagram of the CD7000

Get the real thing. They are usually neither difficult to find nor expensive, and you can sell it again when repairs are done, if you don’t want to keep it.

Martin

[Dillen]

Yes, those bearings.
Not sure if I have a spring.

Martin

[Dillen]

The bearings from Beoparts-shop does not have the extra flange found in some of these motors, but they work fine nonetheless.

Looks like what was once a white version. Look for a stamped letter on the serial number label.
P=Palisander, T=Teak, E=oak (Eg in danish), H=White (Hvid in danish).

Many white Beograms from this time has ended up looking egg-shell or even
light beige from decades of age, sunlight and nicotine.

Martin

[Author]

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