ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Sonavor
Will look into that, I can now compare my machine against Dave's so will post the results, meanwhile I have hit the easy targets for now.....scale illumination and speed lamps now on LED's
Tracking sensor lamp replacement next, Rudi's work again....had to "borrow" Roasties cartridge again to set up the 4-5 turns before tracking commences....all is well.
Ahhh......just when everything was looking good I have discovered that the tracking motor wont drive in reverse when the tone arm is moved backwards! I know it's very unlikely that this will ever be required....I dont know what the engineers at B&O where thinking of when they designed this feature into the tracking circuit...but it's there so I feel the need to bottom out the issue. This represents a fault in almost every aspect of this machine to date......it must have been saving them up over its lifetime, hopefully the photocell is good and the fault lies elsewhere.
Right.....measuring the voltage level at the photoresistor responsible for the return or reverse direction of travel (OR4) I found I was getting a voltage swing from 0 to 20vdc as I moved the tone arm in its direction and light fell on it....the measurement was taken at FC1 the extreme right solder connection below Rudi's lamp box.
Measuring the voltage at the same place on the photoresistor responsible for the forward direction (OR3) gives a much lower voltage level, around 5vdc, for the same movement of the tone arm in its direction.....open circuit somewhere.
Measured the voltage at 1D13 on 1PC which feeds the Base of 1TR33 and was getting nothing.....traced the line back to 6PC and close inspection under my magnifier revealed this very odd break in the copper track, it's not a break in the board that has caused the copper to crack...its almost as though it has been cut through deliberately....but I have a hard time believing that, maybe a sharp blow...something dropped on it perhaps?
Well...whatever the cause I filled it with a blob of solder and measured up once more......now the voltage level measured up very similar to the forward drive photoresistor....and on test the tracking motor now runs backwards and forwards depending on the position of the tone arm...fortunately an easy fix this time.
It looks like someone in the past had a slip of their flathead screwdriver (on that adjacent screw) and it ripped through the trace.
-sonavor
Yes....sounds a more likely explanation, I will press on with the replacement of the trimmers and I have ordered a new aluminium trim for the hood...It's a shame the platter is in such a poor state. I'm also awaiting a report on the condition of the cartridge and new belts will be required.....otherwise its actually starting to look good.
Naturally I don't have the correct value trimmers to hand, ordered some up. Meanwhile I reset the tracking following the disturbance of finding the reversing fault...and as I had Daves cartridge fitted I couldn't resist a quick listen to dark side, played both sides faultlessly.....I'm impressed.
So a 47 year old analog control system design still holds up today Not bad at all.
I probably have a spare cartridge you can have if you want one of your own. I must drop you off the Beovox 5000s as well and pick up the Beolab!
Peter
Your a star.....the Beolab is working fine, has been in service for a couple of months without issue. I have no plans for the month end weekends and I'm home early Friday afternoons, I have an entire weekend to myself the 25th if your about?
Craig
This rather gorgeous looking trim turned up yesterday...……..
That is very impressive. Can you post a picture of the other end? There is definitely a real need for that type of replacement part on our Beogram 400x projects.
The other end......these are available with black or brown text, for no reason I chose brown.
took delivery of a couple of 25 turn pots for the speed control.....
And gave the hood a good polish, one or two marks are very deep and wont come out...I will fix the trim in place right at the end
bored out the stumps of the rubber shock absorbers and using an old O ring made new ones, will trim to size when the hood is fitted
I will check these speeds once I fit the new belts Martin has sent me.....but looking good at the moment
And 45 rpm.....time for a glass of wine
I will join you with my favorite, and thank you for a very interesting thread.
Collecting Vintage B&O is not a hobby, its a lifestyle.
Quality.....what is that your drinking? and I still have a couple of loose ends to tie up, I'm now into my third month with this little devil
Craig: Quality.....what is that your drinking? and I still have a couple of loose ends to tie up, I'm now into my third month with this little devil
Rum and coke, I have used up to 1 year or more on some of mine, and still have some on the shelf to go back to
Now THAT is a hat! Love it!
Jeff
Beogram 4000, Beogram 4002, Beogram 4004, Beogram 8000, Beogram 8002, Beogram 1602. Beogram 4500 CD player, B&O CDX player, Beocord 4500, Beocord 5000 T4716, Beocord 5000 T4716, Beocord 5000 T4716, Beocord 8004, Beocord 9000, Beomaster 1000, Beomaster 1600, Beomaster 2400.2, Beomaster 2400.2, Beomaster 4400, Beomaster 4500, Beolab 5000, Beomaster 5000, BeoCenter 9000. BeoSound Century, S-45.2, S-45.2, S-75, S-75, M-75, M-100, MC 120.2 speakers; B&O Illuminated Sign (with crown & red logo). B&O grey & black Illuminated Sign, B&O black Plexiglas dealer sign, B&O ash tray, B&O (Orrefors) dealer award vase, B&O Beotime Clock. Navy blue B&O baseball cap, B&O T-shirt X2, B&O black ball point pen, B&O Retail Management Binder
Craig: Peter Your a star.....the Beolab is working fine, has been in service for a couple of months without issue. I have no plans for the month end weekends and I'm home early Friday afternoons, I have an entire weekend to myself the 25th if your about? Craig
I'll sort out with Jo and see if I can bring the speakers down on the weekend of the 25th. I'll go though my cartridge collection and pick you out one - I have a distressing habit of giving bits away and have given a couple of 20CLs away in the past so will need to see what I have left! With your permission I will also bring down the BM8000 for you to have a look at - starts clicking if left on which does not seem to be a good thing!! You do realise that the 5000s are rather large? I will also bring down the 2500s so you can try them though as Frede did these for me I am afraid they can only come for a holiday!!
That would be great, I will clear some space to accomodate them and of course I would be interested in taking a look inside a BM8000. I anticipate being home all of the weekend of the 25th so if you can make it that would be very good...and I will give your cubes a run too.
Regards Craig
Adjusted the height of the platter using the suspension adjustments, was fairly easy with the hood bracket removed
Centered the platter as best I could again using the slotted location holes in the suspension springs, not perfect but given her age I think it will do, and the very good news is it looks like I have sourced a replacement platter
Feels like its been a long time coming, just awaiting delivery of a replacement platter and I'm all done......trim is in place and looking so much better for it, wood work sanded down and polished with beeswax...no stain.
Very rewarding given I was close to despair one more than one occasion......thanks guys, couldn't have done it alone
Congrats Craig impressing thread, did you calculate the damage inclusive buying price ?
Hmmmmm…...not sure Soren, will have to think back, the unit itself was quite cheap, it came with 2 beovox 3800 speakers and a Beomaster 3000 amp for £130...neither of which I have any use for to be honest, A replacement platter is on its way at £75....and there where the parts from Rudi and Martin which came to around £230.So with other miscellaneous odds and ends I suppose it came in around £450. Is it expensive?.....gave me the best part of three months entertainment and I now have quite a nice machine...and also I have gained some valuable knowledge regarding the operation of a 4000 too.....though to be fair there remain areas into which I had no need to delve and therefore remain ignorant, I enjoyed it.....even the times when nothing made any sense and finally did, Solderon's B&O training notes gave a good insight and I have forwarded them to Lee for inclusion in the service manuals here.
I admire your perseverance and accomplishment, you get at one point where you dont give up, or you think about throwing it in the bin, and then help from the forum turns up, and you just go on and then decide to go all out on this item until it is where you want it. I have had some of these where cost, time and work didnt matter.
Again congratulations to a successful and interesting thread
Planning to come down on Saturday - will set off in morning once Volvo packed!
Will bring:
Beovox 5000s - a present - you do realise these are not bookshelf speakers!
Beovox 2500 - these can be on loan for a while!
Beomaster 8000 - see if you can stop it clicking!
MMC something - willl see which is worth having - a present
I may bring you some more manuals as you clearly are far more likely to use them than me!
Hopefully will pick up the Beolab 5000 which can take the place of the 8000!
Sounds good to me, will wait in for you......
Platter turned up today......looks fantastic!
Alistair from audio originals provided this little gem, and also loaned me a top of the range cartridge....and to be fair it sounds amazing, wasn't sure I would be able to tell the difference between Mr Roasts cartridge and this one....however I can
I will take extra special care with it before sending it back, Alistair also sent this too......seems he knows I cant resist a challenge, front panels look very tired...text all but worn away....however Frede has replacements it things get that far...I will start a new thread.
Hi Craig,
I’m glad you could hear the difference, the spec is
Nude Micro Ridge diamond boron cantilever
And the end bit is a 3d printed replacement
Best regards Alistair