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General Vintage Technology Discussions For general discussions about vintage radio and other vintage electronics etc. |
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13th Jan 2010, 10:04 pm | #1 |
Dekatron
Join Date: Sep 2005
Location: Seaford, East Sussex, UK.
Posts: 5,997
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Beogram 6006 early microprocessor uses
I am in the middle of restoring a 1982 Beogram 6006 record deck and just got the first signs of life after a full recap and resoldering every joint.
I am sure that as a piece of hi-fi kit it probably rates as junk but that's not it's raison d'etre. It is truly the most crazy piece of over engineering ever. Microprocessor controlled, it has a tangential driven arm, optical record sensing and full variable motor speed control. This was 1982, microprocessors cost £100's of pounds, the IBM PC was just about to launch, and B&O decided to apply the technology to the humble record player. Unfortunately, electronics was not their forte and the circuit is spread over about 6 PCB's, some evidently after-thoughts, lashed together with snubber capacitors all over the place. But it is now spread out in bits on the floor and is happily working again. Press the play button and the motor spins up to exactly 33.33RPM as displayed on the 7 segment LED's, the arm moves across and if the record sensor determines it is not a 33, it switches to 45.00, moves further until it senses the record, and drops the arm. Seems a shame to put it back into the cabinet. Bit of nostalgia as it reminds me of my second job, designing and programming Motorola 6800 process control systems. |
14th Jan 2010, 11:19 am | #2 |
Dekatron
Join Date: Aug 2006
Location: Madrid, Spain / Wirral, UK
Posts: 7,498
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Re: Beogram 6006 early microprocessor uses
BSR or Fidelity maybe, but B&O?
__________________
Regards, Ben. |
15th Jan 2010, 8:10 am | #3 |
Retired Dormant Member
Join Date: Nov 2009
Location: Lancashire, UK.
Posts: 67
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Re: Beogram 6006 early microprocessor uses
6800, a blast from the past, that was one of a couple of processors that needed a 2 phase clock, and wouldnt work without a motorola clock driver.
Citronic made dj consoles with twin decks, about the same time, and it had a 6502 processor, it actually sychronised the bass beat of one deck to the other, you can do that with a pc easily now, I guess it was leading edge then. I had one for repair a while back, its probably still in use. |
15th Jan 2010, 1:27 pm | #4 |
Octode
Join Date: Apr 2007
Location: Hampshire, UK.
Posts: 1,578
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Re: Beogram 6006 early microprocessor uses
The 6006 is the same as an 8000, just with black keys and an MMC20EN pickup instead of an MMC20CL.
It makes most modern turntables sound like silly toys, in particular the speed stability of the platter has seldom (if ever) been bettered. B&O's moving iron pickups were a cut above the rest too, this combined with a short, stiff arm and a freedom from tracking error make for a very serious package indeed. There's a guy in Germany that rebuilds the pickups (to CL spec if you want), with a fresh one fitted I've yet to hear a better turntable. The 8000 was B&O's first tunrtable with a microprocessor but there were others from elsewhere before, the Sony PS-B80 (1978) springs to mind for example. As well as dry joints, change all the electrolytics of 10uF or more (except the one in the transformer box), they are a weak point. Also examine the tacho ring on under the platter, if it's still the original printed type you may find that the ink has started to lift away, luckily replacements can be obtained. |
15th Jan 2010, 4:49 pm | #5 |
Dekatron
Join Date: Sep 2005
Location: Seaford, East Sussex, UK.
Posts: 5,997
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Re: Beogram 6006 early microprocessor uses
This came with the MMC20EN and an unopened box with a spherical version. I'll take a look at the tacho wheel. I just have the micro board to resolder and the couple of electrolytics in that, a clean and regrease, and then I am done.
It's in very good cosmetic order but some little plastic hooks that hold the front panel PCB in place were broken off and will probably be difficult to glue back. All the brushed aluminium plates dropped off as the double sided foam tape had foam rot! I always felt B&O were more for show then function...perhaps unfairly. |
18th Jan 2010, 7:47 am | #6 |
Pentode
Join Date: Jan 2010
Location: Burgundy, France.
Posts: 125
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Re: Beogram 6006 early microprocessor uses
Hello,
I use the Beogram 8000 as a main turntable and it is a joy to behold and to use. I can confirm that it sounds great, better than my (new with RB300) Technics SL-1200 MkII. I use a Soundsmith SMMC20EN which is currently manufactured in the USA. I also know the 6006, I used to have one. It is slightly different in the way it works (counting, carriage motor...) but it sounds the same. Don't give up on it, go ahead and use it! Make sure it is perfectly level and that the suspension is perfectly level. Here's mine: Last edited by Station X; 18th Jan 2010 at 11:30 am. Reason: Linked image converted to a thumbnail. |
19th Jan 2010, 12:14 am | #7 |
Hexode
Join Date: Dec 2009
Location: South Manchester, UK.
Posts: 262
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Re: Beogram 6006 early microprocessor uses
I gave my mum a Beogram 4002 which was released in about 1976, and directly replaced the 4000, from 1975. These were the precursors to the 6000 / 8000 range and the first linear trackers in the world I believe!
B&O have definitely come up with duds through the late 80's and 90's but to me some of their better 80's stuff like speakers (MS150 which I saw go for £500 on ebay last year!!!) record decks and tape decks (beocord 9000) were first class! Tellies also looked lovely picture pretty good and the sound was fantastic - IMO unsurpassed by every telly I have ever herd since! PGL do you realise B&O developed the HX-PRO system and then sold(?) the rights to Dolby after a year of exclusivity? B&O get too much flack IMO they maybe out of reach to the ordinary punter but I know if I had the money a pair of Beolab 9000's would be sitting either side of my telly |
20th Jan 2010, 6:46 pm | #8 |
Dekatron
Join Date: Sep 2005
Location: Seaford, East Sussex, UK.
Posts: 5,997
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Re: Beogram 6006 early microprocessor uses
It's almost done. I have some new foam tape. I have struggled to glue the broken hooks and think I have won (it seems to be a manufacturing fault as they all have identical stress cracks). A little regrease and assembly and I'll test it out with a record.
It came with a 6000 series tape deck, receiver, remote and S80 speakers and stands. I'll gradually work through the bits and recap them. The speakers have the usual foam rot. There seem to be alot of B&O fans out there! |
21st Jan 2010, 5:33 pm | #9 |
Pentode
Join Date: Jan 2010
Location: Burgundy, France.
Posts: 125
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Re: Beogram 6006 early microprocessor uses
Hi,
I too have the Beomaster 6000 and matching Beocord. Both units sound great and I can only encourage you to refurbish them; it's totally worth the trouble (and they will be troublesome to fix, I can assure you). You will understand once they are fixed! |