BeoGram

Re: Shot Beogram 4002 bearing?

chartz — Mon, 11 Oct 2010 06:50:26 GMT

Step1:

How are you doing anyway?

Fine, thanks!

This bearing is a bit special to say the least! It only has one sintered bronze bearing (1.5mm thick!) at the top of the pit and a one-point contact at the bottom, hence its "wobbly" nature. Once it has settled it remains stable, but the bottom part of the shaft is allowed to move when the platter is pressed on a side!

I wonder whether this is wanted to reduce contact areas. It is not very effective as my BG8000 bearing will rotate much, much longer when launched by hand.

As far as the electronics are concerned, I've just ordered BC142/143 transistors to replace the defective ones driving the carriage servo motor.

Jacques

Re: Shot Beogram 4002 bearing?

Step1 — Mon, 11 Oct 2010 05:56:32 GMT

It won't until the carriage moves - the switch is mechanically 'active' as Graham says and when you hit start you are in effect operating that switch remotely, then by the time you let go of start key the switch has taken over and completed the circuit.

If you press start very quickly on a working 4002 you might find the machine turns on but turns off again because the switch was not quite deactivated - especially if the belt is not up to scratch.

Regarding the spring these bearings have no loose parts in them at all, so no!

How are you doing anyway?

Re: Shot Beogram 4002 bearing?

chartz — Mon, 11 Oct 2010 02:54:05 GMT

joeyboygolf:

My 6000 clicks, which I think is the end stop microswitch deactivating!

Yes, but it doesn't click pressing "PLAY/START" in itself!

Back to the topic, I read in a post or two that there should be a spring inside the bearing? Maybe around the recess at the bottom of the shaft?

Jacques

Re: Shot Beogram 4002 bearing?

Dillen — Sat, 09 Oct 2010 09:52:11 GMT

Oh yes, that could produce a click.

Martin

Re: Shot Beogram 4002 bearing?

Step1 — Sat, 09 Oct 2010 05:54:50 GMT

Yes I think you are both sort of correct - kind of a half click!

BTW has anyone thought of making these decks quieter like the 4000 was? The 4000 had a superior servo motor, silent leaf switches with which I doubt there were any major problems the only audible bit was the speed change which could possibly be substituted by a couple of reed relays? I have to say I am very tempted, maybe with my 4004...

Re: Shot Beogram 4002 bearing?

joeyboygolf — Sat, 09 Oct 2010 05:34:28 GMT

My 6000 clicks, which I think is the end stop microswitch deactivating!

Re: Shot Beogram 4002 bearing?

Dillen — Fri, 08 Oct 2010 03:39:23 GMT

The platter should start rotating and the carriage should start moving left.
No clicks.

First click will be from either the solenoid lowering the tonearm (in the case
of a 12 inch record) or the speed switching relay (in case a 7 inch
record (or no record) is found).

Martin

Re: Shot Beogram 4002 bearing?

Dillen — Fri, 08 Oct 2010 03:36:01 GMT

No.

Martin

Re: Shot Beogram 4002 bearing?

joeyboygolf — Fri, 08 Oct 2010 03:24:59 GMT

Yes!

Re: Shot Beogram 4002 bearing?

chartz — Thu, 07 Oct 2010 13:43:02 GMT

Hello, Should I hear a click when I press play? Jacques

Re: Shot Beogram 4002 bearing?

Dillen — Wed, 06 Oct 2010 15:45:37 GMT

I believe so.
So you have two faults still. Isn't it wonderful ?

Martin

Re: Shot Beogram 4002 bearing?

chartz — Wed, 06 Oct 2010 15:23:47 GMT

Dillen:

The servo motor should start rotating when you press START

Even if the IL1 lamp is dead?

Re: Shot Beogram 4002 bearing?

Dillen — Wed, 06 Oct 2010 13:51:50 GMT

The servo motor should start rotating when you press START (or PLAY as the lettering says on some decks).
If it doesn't, you will have to find out why.
Check for cracked solder joints at the main board edge connectors.
Check the power supplied to the main board.

Martin

Re: Shot Beogram 4002 bearing?

chartz — Wed, 06 Oct 2010 13:26:13 GMT

Thanks. The belt is in place and the carriage motor doesn't turn at all (no voltage arrives at it either).

There is 5v at IL1 but I can't see any light. Should I see some?

Jacques

Re: Shot Beogram 4002 bearing?

Step1 — Wed, 06 Oct 2010 13:13:02 GMT

Check that the servo belt is still in place and not slipping under the right hand panel.