[spassmaker]

Hi there

Really no one?

Does anybody know about different Codes maybe for older models?

Have already found the usual 1271 and 1207 both did not work 😢

Maybe renew the 8 PIN static RAM?

Any help would be appreceated.

Thanks a lot.

Kind regards

Christian

[spassmaker]

Bad news….

For some saftey reasons I put in a new battery, now both uPc boards have the same behaviour, even I swap the EEPROM’s.

Co.de is displayed and nothig there to get rid of this.

 

Oh dear what have I done wrong?

[spassmaker]

Hi

J6st came back from a short journey where I bought a used BC 9500 for a couple of €’s

Took me 2 hours, the dead Beocenter was unplugged from the mains so long.

Tried once more the ” code routine” but nothing happens.

So I swapped out the uPc- board (No 40)

Beocenter runs.

Put the old EEPROM into the “new” uPc board,

Beocenter runs.

Put back the old uPc board and tried both EEPROM’s

Beocenter is not working.

So there must be a issue with the uPc board. Never thouhgt about this, never had problems with these.

To be continued….

 

Kind regards

Christian

 

[spassmaker]

Really no one?😔

[spassmaker]

Hi Jacope

Did you renew the cap on the prcessor-board (47uF if I remember) in the uPC – can?, quiet important.

Usually there are two flat wires to the front panel.

One is just for the display , the other for the buttons.

The flat wire for the buttons is only sticking in the mainbords connector, so high risk of pulling it out a little bit while handling the boards and there is no connection to one of the outer wires, so please recheck these.

Another fact is when already pulled out to missalign the wires while sticking back into the connector so there are maybe two of them in one hole. Don´t ask me why I know this ;-))

Did you measure the voltage for the LDR in the frontpanel?

This could cause lot of funny problems if not aligned according the SM.

So first is to bring the Beogram back to life, after that we could look for the backspinning, which is quiet usual a little bit as the the unit is plugged in, but not for 3 seconds.

Mine makes just about a 1/4 to 1/2 round backwards when plugged in.

Kind regards

Christian

[spassmaker]

Hi

Found the screws under the rubber ring, all ok.

Thanks again

Christian

[spassmaker]

Hi

Thanks for that, I´ ll try next days.

 

Kind regards

Christian

[spassmaker]

At first I would replace the platterbelt with a new one, if there is still wow you have to dig deeper.

Listen without amp but record on if there is some scraping noise from platter to other parts inside.

Beoparts (now: Danish Sound Parts) provides the right platterbelts

If you are already working on the turntable maybe you renew the belt for the tangential drive too.

Kind regards

Christian

[spassmaker]

If you adjusted the pot wich is discribed as MOT you would have chaged the amplitude of the platter motor.

Nothing related to the differential circurit as far as I know    😉

Maybe you puzzeld a little bit at the other pot’s too?

 

Kind regards

Christian

[spassmaker]

Hi

I’ll try to help a little bit.

P7 – 12 and P 7 – 6 go to ground because

P 7 – 6  is Ground

P 7 – 12 has a conection to ground via the motor coils ( 0 L 1)  related Plug ( P 4 -2; P4 – 5) . Have not measured the coils so far but could be in around 200 or less Ohms.

So desolder one leg of D42 and check for a short.

 

A common issue, what I had already twice for what reason ever, is D 20.

This is a Z Diode  6,3 V and a protective diode for the 5V of Processor and so on.

In case of a overvoltage of the 5 V line this diode is shorted and the fuse could trip to protect the connected uPC and others.

So check D 20

 

Kind regards

Christian

[spassmaker]

Hi Ary

Ordering a capacitor kit from Beoparts (now: Danish Sound Parts)is not stupid, i my opinion it’s the best way to get all caps in a set for a dedicated restauration project.

Beoparts (now: Danish Sound Parts) is providing a PDF with information for your ordered Capacitor kit:   “Instructions can be downloaded in pdf-format using link(s) provided in the order confirmation email. ” seen on Beoparts homepage (now: Danish Sound Parts).

 

 

About your +21,3 Volt at C29, it is the place where the + 15 and – 15 Volt are generated.

What sometimes happens is that the cap was desoldered and “forgot” how it was mounted, so it could happen that a cap is mounted reversed. The printing on the PCB’s is sometimes simply wrong.

So take care that C29 is looking with it’s MINUS to the anodes of the rectifier D21 – D24 recheck C27 to it’s polarity.

 

I don´t excactly know, but C 27 is the cap with the 3 pointed ring underneath. These 3 points are connecting 2 GND points on the PCB together. Recheck that the GND points around the two 2200 uF cap’s are ok.

If the two GND points are not connected one point has a”floatig” GND and can cause several issues.

Long story told short:

https://beolover.blogspot.com/2017/05/beogram-8000-recapping-main-board-and.html

 

Kind regards

Christian

[spassmaker]

Hi Jordi

The Capacitor that you mentioned is the last I would change because this is the Phase Cap for the Platter Motor mechanism which normally lasts very long.

If you got no LED I would resolder ALL solder joints of the plugs on the PCB’s an performing a recap of ALL electrolytic capacitors on thePCB’s.

Usually after that the BG 8000 will start up again…following issues have to be inspected later.

 

Here, on Beolovers site, you will find a bunch load to read about restoring the BG 8000

https://beolover.blogspot.com/p/beogram-80008002-restoration.html

let us know about your progress

Kind regards

Christian

[spassmaker]

Hi Gunnar

My question is if the slowing down is sometimes for a second or slowing down for longer time.

first case from my experience there is a problem with the spark snubber diodes (TVS diodes) in the motor. Find out detailed information here:

https://beolover.blogspot.com/2021/12/Beogram-4002-dc-motor-spark-snubber-replacement.html

second case  from my experience are the dryed out motor bearings. Detailed information here:

https://beolover.blogspot.com/2023/11/beogram-4002-dc-platter-motor-restoration.html

and here:

https://beolover.blogspot.com/2021/10/beoparts-dc-motor-bearings-tested.html

 

Kind regards

Christian

[spassmaker]

Hi

Did you  replace the foam and gaskets? Could be airventilation caused by gaps between the amp module speaker module or top module with pipe.

May be that a PCB is ratteling  because of a missing screw or a broken screwpost. Often the screwpost break while tightening the boards or handling, or screw isn’t fully tightened.

Why the ratteling sometimes is audible and sometimes not is quite a mystery.

did you crosscheck the”bad” woofers in the”good” speaker set? For me it’s a bit confusing how you did the test ;-))

If you push gently the bad woofers is there any scratchy feeling?

Try to test the woofers out of the speaker with reduced volume and listen to the bad ones and good ones > any difference?

Good luck

Christian

 

[spassmaker]

Maybe you get some more information in this discussion:

https://archivedforum2.beoworld.org/forums/t/10293.aspx

Lot to read and some pictures.

Kind regards

Christian

[spassmaker]

Hi

1

I could not find any hints in the service manuals (even BG 4002 type 5501) where is discribed to change the fuses to 500 mA, so I would keep the 250 mA slow blow and check it out.

Of course the Ohm’s law says half of voltage means double of current with same power output

= 500 mA

Maybe Martin has further informations from Service manuals which I’ve not seen.

The worst thing what can happen is that one of the fuses is blown and the Beogram stops working.

Tonearm will lift at power fail.

 

2

Regular glass fuses, slow blow

3

Living in DE so no experience

4

you could use an adapter or mount an UK plug as you like, I would use an adapter so all keeps original. The plug should have no effect to the sound because there are no RIAA amplifiers or somthing active parts like that in a BG 4000. The High end authority would say something else ;-))

 

Kind regards

Christian

[spassmaker]

Martin

Thanks for your reply, you’re such a great database ;-))

Checked it out yesterday and the BM 8000 shuts of after about 30 miutes, so all is working.

Thought it would shut off after 5 miutes or so.

 

Have a nice day

Christian

[spassmaker]

Hi Derek

Thanks fore information.

I already saw these offers in the www.

In between I desoldered all IC’s from the PCB  and tested them on a breakoutboard.

Found one mor defective FCH 131 wich had an steady High level on one output.

I decided to solder all back in and only leave 3 IC 5 open  because the there are only two and three inputs of the NAND’s used.

I will try to rewire an CD 4012 an look what will happen….fingers crossed.

Still waiting for deliver the CD4012, when they arrive I will report.

The failing of the  IC’s was, in my opinion, caused by the Z Diode 2D4 6,8 Volt.

This diode was loose in the solderjoints by some strange human activity. If it’s loose or not connected anymore, from my knowlege, the voltage on Emitter 2TR6 is raising near to the input voltage  Collector 2TR6 (haven’t measured what comes out from the bridge rectifier) and fries the IC’s.

 

Kind regards

Christian

[spassmaker]

Really no one ??

Kind regards

Christian

[spassmaker]

Thanks for the picture

Any further information?

How to?

Where to get?

What about black lettering?

Kind regards

Christian

[Author]

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