Just found this forum, looking for info on how to get my Beogram 8000 running well again, and wanted to share what I did to my Beomaster 8000 about 10 years ago: LINK It shows my struggle repairing the amplifier, which got far too hot on one side, without a service manual. (Yes, I succeeded.)

Can I say I'm not overly impressed with the insides of these machines? All these separate little circuit boards, messy cables and connectors, shudder! The Beogram 8000 circuit board has some resistors and caps additionally soldered on even, and two little circuit boards bolted onto the main one. For a machine this price I'd have expected a more polished product inside, I guess. An why on earth is the din-output on the entirely other side of the machine???

rick jansen 

Hi Rick and a warm welcome to Beoworld.

An excellent first post and most welcome it is too, I am sure this will be of great use to many owners of these excellent vintage Beomasters. I have edited your post slightly by inserting a direct link to the site with this info - hope you don't mind.

What is the problem with your BG8000? I'm sure we can help sort it out for you.

Chris.

Thanks!

My Beogram 8000 suffers from, as usual: irregular speed. The tacho disk has a thin plastic sheet that is separating from the disk at the underside, although the actual pattern is on the top side. There are some cracks in the pattern there, and also some crackling in the clear plastic of the disc itself. I tried mending the pattern by blackening some cracks with a CD felt tip pen, but it has not improved. 

If I counted right, there are 144 slots in the disk, so 288 signal edges. If just one edge is missing or uncertain that is a 0.34% error already, which is terribly audiable. It sounds as if my Beogram had too much to drink, although technically it's called wow&flutter, I believe.

Needless to say I ordered a stainless steel tacho disk and caps replacement set from the in-house guru :-) (most grateful)

By the way: do you guys clean and (re)lube the worm of the tangential traction? And with what? I do have some ball-bearing grease for my bike, but I'm not sure if that fits a Beogram's worm. Or better leave it alone? (I know oil is NOT the stuff to use here.)

rick (eagerly awaiting the mail missus)

Rick,

The carriage drive shaft should be cleaned off any old lubricant plus any dirt and dust that have accumulated here.
Then you can give it a few drops of acid-free oil (sewing machine oil) and let the carriage travel the whole distance back and forth a couple of times.
Most often, this will losen more dirt which then needs cleaning off.
Repeat a couple of times and give it a final couple of drops.

Silicone grease is also good but won't losen- and allow the removal of old lubricants the same way.

Martin

White lithium grease works well too.

Derek

Hi Rick:

Well I think you really need to look at B&O's design challeneges.

First and foremost the design imperative was the cabinet. The engineers then had to figure out to pack all the electronics inside (typically B&O) very odd shapes. This is not easy to do if you consider the wedged shape of the BM 8000. The massive toroidal transformer alone takes 1/3 of the entire cabinet volume. Further to this the BM8000 with its microprocessor, digital display, tuning and optical encoder was a very advanced piece of equipment for 1980 and had to be implemented entirely in high current TTL logic which takes up space.

For how complicated the BM8000 is I think it is an incredibly thought out design. The electronics are all modular. Each pre amp, amp, tuner, microprocessor had its own board. And as you pointed out in your webpage, they thought about making it service friendly with the recessed panel ledge. Also the use of molex connectors and ribbon cables makes servicing so much easier.

Most disappointing to me about B&O equipment is their circuit boards. I never understood why they chose to use that cheap brittle phenolic board material. For the price, they really should be using epoxy glass boards which are much more rugged. It appears that all of the quality went into the aluminum and glass cabinet structure and the electronics took a bit of a hit.

Derek

Silicone grease? If I understand  http://en.wikipedia.org/wiki/Silicone_grease  right, is that the same stuff as the white heat conducting paste for use with heat sinks? I do have a small tube of that. It doesn't exactly feel like a "grease" though...

rick 

I have a hunch that this Wikipedia article is full of it. The heat sink goo is silicon paste, and will harden for sure. The stuff you use for lubrication is silicone grease...

-mika 

I couldn't agree more, it's DEFINITELY NOT the same.
Silicone grease (and lithium grease) will not harden.
Heat sink compound is not a lubricant.

I'm afraid that you cannot always trust Wikipedia. 

Martin

Rick, given your last name i draw the conclusion you could be Dutch ??

The thing is, here in NL i bought a can with silicone (oil) spray to be found in the bike section of the Hema (department store).

They also have a similar thing for bike-chains, i figure this is not too different from the other one.

After cleaning the mechanics to be lubricated i spay some of this on a cotton q-tip, than wipe that onto the parts to be lubricated, let it dry a bit and wipe away any access oil, this seems to leave a nice thin lubricating layer which is not sticky also.

Maybe in the UK (or wherever you are if not in NL) you can find a similar product in a bike shop...

From what i know the good thing with silicone oil is that it does lubricate but doesn't stick or drip or gets hard (like old grease) and isn't ''agressive'' to materials like plastics, nylon...(but people: feel free to comment on this).

Hi Auric,

Oh, I understand the challenge of bringing a finished product to the shops, and the Beomaster 8000 sure is an incredibly complicated one. Still, if I look at this "cable salad" it does not feel exactly, eh, as I expected. The cabinet inside does have quite some space actually, it's a very BIG machine! I can imagine though that in the days of circuitboards with a hand made layout things weren't as flexible as they are today with computers and stuff.

The gorgeous aluminium and glass outside indeed isn't exactly matched on the inside. And a polystyrene plastic chassis? What were they thinking.. And joining the display print to the microprocessor print just with some connectors and no further support? (Yuck!)

Anyone an idea how many Beomaster 8000's were actually produced? The whole system (beomaster+beogram+beocord+beolab+cabinet+speakers) cost about the same as a small car in those days.

rick

Hipaul,

As Dutch as Hemaworst ;-)

I am a bit surprised by this oil-thing though, I always understood that bearings like worms and ball-bearings should be lubricated with a grease, and not oil... The service manual for the Beogram 6000 says: Rocol MTS 1000 diluted to oily viscosity with Esso NUTO H 44. It's never simple is it.

This Rocol is "High load molybdenum disulphide grease for heavily loaded and slow moving bearings especially plain bearings".

NUTO H is "Exxon Nuto H Series oils are premium quality anti-wear hydraulic oils intended for industrial and mobile service applications where anti-wear lubricants are required".

rick (should we start another thread for this?) 

The 8000 series has always been a bit of an enigma to me. On one hand, the electronics and ergonomics do seem to have been well thought out and when new, these were stunning systems. However the manufacture seems to have been, as stated above, less than perfect with a number of cost cutting measures which are now causing problems.

This is one of the reasons I prefer the slightly older era - the Beomaster 4400 , Beogram 4000 and Beolab 5000 system are beautifully built as well as sounding fantastic. I still may get rid of my 8000 system as I use it less and less.

Rick, if you want some silicone grease I can send you a small pot FOC of course (all part of the Beoworld service).

Drop me a PM with your address and I'll pop it in the post for you.

Chris.

Rick:

I understand your point and agree with you on all of the loose wiring. The way some of the boards were "jammed" in there does seem a bit like an after thought such as the little mains transformer sitting directly under the display board insulated only by a piece of card board etc..

If you listen carefully you can hear the microprocessor's clock leaking into the audio path. This I'm sure this is a byproduct of the construction and the "cable salad." I'm only thinking what could have been a better alternative though?

The entire chasis of the 8000 series including M150 speakers were all made from this composite material. Is it really polystyrene though? I don't know my materials well enough to tell, I would have guessed an early form of graphite. If that is the case, it may have cost more than aluminum or steel.

I do think however that it was a good choice of materials given the shape that they were going after. It reduces weight and more importantly the chassis doesn't flex. Fast forward to the Beocenter 9500, this system's chassis is made from steel and it flexes. Whenever I pickup my 9500 I hear it creaking. The BM 8000 is pretty sturdy in this regard. This material however does get brittle with age.

I enjoy it for its looks...I'm hoping to change the capacitors and upgrade the opamps in the pre amp someday. Hopefully I can get it to sound better. Its a bit lack luster in sound.

Derek
 

ipaul:

After cleaning the mechanics to be lubricated i spay some of this on a cotton q-tip, than wipe that onto the parts to be lubricated, let it dry a bit and wipe away any access oil, this seems to leave a nice thin lubricating layer which is not sticky also.

This is the key when using silicone based lubricants - never spray it directly on the target. That stuff is vile. Leave it on the table and it will climb up the walls on its own. Get some on your hands and you will slip in the bathroom the next day. Apart from that, it's quite useful for may purposes
 

That will teach you not to walk on your hands in the bathroom.

rick 

Well, the mail missus delivered the tacho disk and caps replacement set in very good order, so Saturday was spent putting things into place. Some studying revealed you can simply turn-slide away the tacho sensor with that brass lever, allowing the center spindle to be lifted out, careful not to touch the grease thats still amply on there. After some careful poking with a potato peeling knife I managed to pry off the toothed steel placeholder ring off off the original tacho disk by releasing each prong. Is that the correct word? Hmm, yes. The new disk fits seamlessly. Nice! Now get that teethed placeholder ring back on. Not easy, not enough fingers. I used a small glass bowl to push it "on". That worked.

The caps replacement chart revealed I also needed to open up the CPU box. Urgh. That is connected to the main print by a connector where simply the separate wires of the ribbon cable are inserted into. Nice. Did they really solder a separate capacitor to each pin of the cpu? Yes, they did. Oh, and how lovely to see the lid of the box is also the heat sink for the cpu. Quite a lot of silicone grease, eh, paste too!

As mentioned before, there are lots of wires and enormous lengths of various cables. Except between the panel with the buttons and leds and the print. They must have nearly run out of cable just before they needed to connect the leds and print in my beogram. And such a wonderful construction it is too, the led panel is sort of held in place with the most sloppy copper spring they could make. A miracle it stays in place at all. (They ran out of screws too, apparently.)

Replacing the rest of the caps went fine. I managed to not reverse a single one, I think. The only ones I didn't replace are on a small board on the floating chassis, as I don't see how I can reach that. Maybe later some time, when I regrease the worm. (Didn't touch that now.)

Assembling the machine again took some time, especially since I managed to have taken the hood off, and I needed to figure out how to reinstall that again, without the service manual or breaking the hinge, or anything else. Does that steel spring need to point up or down? Up apparently. What does this adjustment screw do? And who ever came up with the idea that you can affix a nice bit of aluminium to that separate hinge with sticky goo stuff? The same sticky goo stuff they used to stick the alu around the platter to the frame, and that is less sticky after 25 years to do it's job, apart from annoying the owner/service engineer by crumbling all over the place. The same sticky goo stuff they used to stick a bit of steel sheet (now loose) to the alu bit below the pickup arm assembly. And that plastic strip at the back that keeps the hood's hinge in place could have been made a tad thicker, and with more reassuringly sturdy clips. I managed to not break one off, fortunately, this time. Why wasn't this made out of aluminium? A little alu strip and some screws cannot cost THAT much?

All done. Hmm.. the platter is not exactly horizontal is it? It's above the top of the beogram, and a bit tilted. Oh dear,  did I do something wrong with the central bearing's nylon disk? Remove platter and sub-platter again, slide away the tacho sensor, check nylon bearing, no that seems alright, and the correct side up too, put spindle in place, sub-platter and platter on top. Mmm. Then I remembered I had taken the little hooks off off the springs of the subchassis, so I probably needed to readjust the springs. You know, those hooks that other people use to hang christmas baubles in the tree.. Yes. It's much better now, though still not entirely satisfactory. Something to fix later. First see if it still works at all...

Time to switch it on! Press "Turn". And YES! It's spinning! But, eh, a bit fast. No, very fast. This can't be right. "STOP!" Aha, forgot to slide the tacho sensor back in place. Platter off. Subplatter off, slide sensor back into place, wipe sweat off, put platter and subplatter back on, "Turn". And it works FINE! No more flutter, just a lot of wow!

rick (what a day, slept like a log I can tell you) 

Great to read stories like this !

The subplatter has three little keys that will fit into matching cutouts in the spindle. If they are not fitted correctly the platter will be off horizontally.

Hopefully the wow that remains is of the WOW! type rather than the type you use electronic instruments to measure... 

Martin

The subplatter rests ok on the spindle, if that wasn't okay the platter would be tilted far more. This was just a few millimeters difference at the edge of the platter. But hey, we're purists here, aren't we?

Is turning the screws on the springs the way to adjust a  slightly tilted platter..? 

Should the hooks from those springs that hold the sub-chassis, from these pins: _^_ be on the INSIDE of the hole, or are they on the outside of the spring? Attempt at some art:

     
 _
|=|========================
  |
  |
 _^_
  
or:
  _
 |=|========================
 |
 |
_^_

Yes, the leaf springs are adjusted by the screws, that's the way to set the platter height and correct for any horizontal tilt.

I am not sure about the little C-hooks. I've seen them mounted both ways.

I like to mount them all the same way, but I don't think it matters that much.

If you glue the C-hooks to the _^_ hooks in an upright position using a tiny amount of contact glue or similar, they won't fall to the bottom of the deck while assembling.

Martin

Oooh, that didn't happen to me. Not-at-all. Honestly. Fingers crossed.

rick (<- liar) 

Thanks for all the help, it runs absolutely fine again, and with the positive, happy, WOW! only, and unmeasured flutter only.

What a great thread Rick. I haven't got an 8000 (yet) but I know where to come when I need to open it.
It has been a pleasure reading your posts. Thanks!

Andy T.

Uh oh, I'm afraid it's time to open up my Beomaster 8000 yet AGAIN, after 10 years: when I switch it on the relays click-click-clickclick-click-click-clickclickclick before deciding to really switch on. I guess some voltage isn't coming "on" in time, any more. Just before I start digging, please yell if you experienced this too, to point me in the right direction? I noticed that there's a "delayed relay circuit" with a direct link to the main amp's right channel, so I'll look there first.

(Is a caps set available for this apparatus maybe? I enjoyed the one for the Beogram a lot, especially with those nicely coloured pictures.)

Thanks!

rick jansen

Hi Rick, 

If the caps haven't been replaced already, they really should be.

The relays are for the soft-start and safe shutdown circuits and anything amiss here should of course be corrected.

Readymade capacitor kits are available for the Beomaster 8000, Ebay or directly from me

Martin