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
I just received a BG4002 AC from South Africa, for restoration. It appears to never have been worked on, in excellent all-round condition.
Here is the challenge for those with SHARP eyes.
It is NOT a standard BG4002 AC, by any means.
This is a very unusual piece, with 2 components which are hardly ever seen in the BG4002/4 or BG6000.
I probably worked on one of these special units as a young apprentice B&O tech, over 40 years ago, but since I started CondorAudio in 1998, I have never seen this specific special version.
Who can identify these special ingredients?
Menahem Yachad: Who can identify these special ingredients?
It is a DC version and has a CD4/RIAA pcb?
Vintage Bang & Olufsen
Opto reader on the threaded shaft.Leads soldered to main board rather than plugged.Carriage position switches rather than an opto ruler.
Martin
I should have excluded you! There's not much which you haven't seen.
No, it's not a DC version - the large AC motor and the big 4 caps are clearly visible.
So what's so special about this unit?
It was one of the very first BG4002's ever made, immediately after the BG4000 stopped production.
There were some components left over from the BG4000 production.
One of the most common leftover BG4000 parts which were transferred to the 4002 production was the 4000 platter, which has the strobe markings underneath for the neon lamp (abolished on the BG4002)..
But on this unit, there is also the BG4000's Carriage position switches and associated PCB, instead of the later perspex opto-ruler.
As soon as I noticed that, I automatically looked for bits and pieces of the 4000's red indicator slider.......
And of course, as Martin also identified - the lamp on the threaded shaft whose associated circuit counts the revolutions of the plastic wheel.
So this unit is actually a hybrid BG4000/4002.
What over-engineering!
It all disappeared shortly afterwards, on the first full BG4002 production (no more BG4000 leftovers)..
I love working on these machines - a real pleasure!
Hi Guys!
I am a bit of an electronics virgin. Am working on a beolab 4000 with a spot of foam related damage......
fkatze:
But I finally put an order in for a new board and keypad for my beocord 8000 to be printed on a commercial printer using better material than I can do. Found a place with a more reasonable price, and if the test order works out, I hope I'll be able to offer a plastics kit for the BM2000 for anyone interested. I should receive the test parts in about a month.
Here's hoping.
How do you people deal with this kind of scrathes and wear outs? Paint, sanding, acid or something else? Tips?
blah-blah and photographs as needed
Menahem Yachad: And of course, as Martin also identified - the lamp on the threaded shaft whose associated circuit counts the revolutions of the plastic wheel.
It doesn't actually count. Its output is sensed and filtered for fast pulses and (in some versions) held up against the carriage position to determine when the needle runs in the lead-out groove.
Orava: How do you people deal with this kind of scrathes and wear outs? Paint, sanding, acid or something else? Tips? I use a silver cleaner product called Argentil. No idea if that’s available abroad. Silvo perhaps?
I use a silver cleaner product called Argentil. No idea if that’s available abroad. Silvo perhaps?
Jacques
Magic eraser, perhaps, for the superficial dark marks.if the scratches are deep, the answer is you don't deal with it, instead replace the damaged parts.
Yes, you are absolutely right, but in this case I should scrap the whole thing, what I dont like to do. Aim is just a make it usefull.
Hi, I was working on imprving my BeoLab 8000 frets. I used 'Akustikstoff' and double sided thin polyester HPX 'Ultra Mount tape'. The Akustikstoff fabric for me works much nicer than the 60 denier tights I used before (less stretch) and I am pleased with the result that has a bit more texture. Further the LEDs are a bit better visible. The tape is extremely sticky. I used it on the outside and the inside of the sidesSome photographs below.
Also did my BeoLab 6000s that were a bit easier :-).
Regards, Johan
Hi Johan,
Good job! Do you have any experience in cleaning dirt spots on the fabric (BeoLab 6000/8000 speakers) ? I have a pair with white fabric and I want to remove the dirt, but I'm looking for ideas how to do it best.
Living Room: BeoVision 7-55 MKII / BeoLab 7-6 + BeoRemote One + 2x BeoLab 8002 + BeoLab 2 + 2x BeoLab 6002 + BeoSound 9000 MKII + BeoSound Core + BeoCom 2 + BeoLink Gateway + BLC NL/MLMaster Bedroom: BeoVision 11-55 MKIV + BeoRemote One + 2xBeoLab 6000 + 2x BeoLab 4000 + BeoTime + BeoCom 2Guest Bedroom: BeoVision 6-26 MKIV + BeoRemote One + BeoCom 6000Home Office: BeoVision 10-32 + BeoRemote One + DVD1 + BeoCord V8000 VHS + BeoSound 8 + BeoSound 1 (CD version) + BeoPlay A1 + BeoCom 2Sewing Room: BeoVision 10-40 MKII + BeoRemote OneBathroom: BeoPlay M3 + BeoRemote One
Hi, thanks!
I have no experience with cleaning (white) frets, mine were so bad they needed to be replaced. But I do remember threads like this one https://archivedforum2.beoworld.org/forums/p/46169/332869.aspx#332869 where the frets were washed. With these large frets this probably will be probably best done in the bathtub :-).
Good luck! Let us know what you will do. If things go really wrong you can always recloth.
Regards,
Johan
Well, this is confusing.
While reading this https://archivedforum2.beoworld.org/forums/p/46214/332959.aspx#332959
I did dig out one of those mechanisms and do some measuring. Beocenter control feeds 3,7v 38mA under load to motor and that does not change when motor is oiled and cleaned like gear wheels. But when I did feed 4,5v from outside supply to test meanings, it had no problem to play and wind.
Now confusing part is that after that test it did work with out problems with it's own supply too. Nothing has changed on beocenters power feed.
EDIT: Back to problematic
I had a delivery today
Yes, I know they are white - nothing a bit of dye can't fix. The keypad is still really a prototype as all my home prints break the retaining tabs almost instantly when test fitting, they just don't have the flexure required out of my Ender3. This seems much more promising.
The tuner board is basically be done, as I have tested fit extensively, albeit printed as two parts and glued together - not a long term proposition, but fine for prototyping. So this should be 100% fully functional. If anyone wants one, let me know.
Possibly bad idea for long term usage but it gives me change to make adjustmenst until I get the real thing.
I just fixed a second LC2 light dimmer with the same problem as before.
Sold as non-working, it was again resistor R3 that had gone open. No visible damage anywhere, and a simple replacement of the resistor (5.6ohm, 10% 0.4W) bought the unit back to life.
This unit had some issues with the contact between the dome and the contacting rubber on the PCB. I used some conductive silver paint on the contact surface on the dome and with some trial and error it now works pretty much Ok.
Isn´t that beautifull? And it works like a clockw... like a Beogram. Thankyou to Solderon for perfect pulley.
I have just been fixing the two-way function in my mint BL5000 - one that I have kept safely in a box for quite some time!
I used Leslie's excellent notes here: https://archivedforum2.beoworld.org/forums/p/9016/89803.aspx#89803
and MartinM's photos from the old forum here: https://archivedarchivedforum2.beoworld.org/members/MartinM/files/Beolink5000_5F00_1b.jpg.aspx
To be honest my soldering isn't the best - shaky hands and no confidence whatsoever! It was made more tricky because the screen is superglued in place (one of my earlier fixes) hence I had to prise the upper PCB upwards slightly, disconnect the lower PCB's ribbon connecter and then fold the top board over and back on itself - a high-risk procedure knowing how fragile the screen connectors can be!
I used just Tantalum capacitors - the 22uF nearest the screen was slightly too large but I just managed to squeeze it in.
I was amazed to see the following results - I am very pleased indeed: (Many thanks to Leslie (if he still visits) and MartinM.)
Deleted - moderated post that magically 'appeared' one week after posting, by which time I had re-posted (as seen below).
A few recent, relatively straightforward repair jobs:
Firstly, I replaced a contact foil in a Beo4 – I haven’t posted photos because that’s been covered several times before. It was actually to repair a Beo4 used by my 85-year-old auntie with her BV8. Every few years hers ‘goes faulty’ so I send her a replacement from my stock and repair the damaged one in slower time. Last time it was a cracked screen, this time I suspect there was some kind of spillage. Initially I cleaned it up internally and used a little isopropyl alcohol, and for a while it would work. A few hours later it started sending false transmissions (red button) and the buttons became unresponsive. Eventually I replaced the contact foil and it is now working well. I will put it to one side to send back to her when the next accident occurs!
Today I received a supply of ‘rubbers’ from Martin/Beoparts 😀 Fast delivery thanks Martin!
First job today was to replace BL1000 feet. This is very straightforward but it is always worth taking the remote apart to remove the little bit of old rubber that otherwise rattles around inside. Top tip: Always replace in pairs; if you only do one then it will stand proud and cause the remote to wobble on a hard surface (ask me how I know!) I replaced the top two, and found that pushing them into place with a wooden cocktail stick works very well without damaging the rubber. Parts here.
Second task was new rubber bumpers for the dustcover lid of my Beoworld Prize Draw win ‘ex-007’ Beogram 6500. Only one had come off but again I replaced both. As suggested on the Beoparts site, I used a 2mm drill bit to carefully remove the old rubber and then pushed the new ones into place. Parts here.
Next task is to replace the transformer rubber bushings in my Beocenter 9500 – hopefully to reduce the humming that is amplified by the wooden shelving unit that it sits on. I will let you know how I get on and maybe even post photos of the process. Parts here.
So today I replaced the transformer rubber bushings in my Beocenter 9500. It was a little awkward to lift the transformer in order to put new bushings underneath, but otherwise quite a simple task.
First put the BC9500 in the service position (glass panels removed, of course!). I then removed the little plastic cover at the rear for access to the transformer (just undo the two visible screws):
Here's the transformer from above with the old bushings in place:
And with the long screws, washers and top bushings removed. There's also an annoying black earth cable tucked down the left hand side, not visible in this picture, and connected via a spade connector to the bottom chassis - this needs to be undone in order to move the transformer upwards.
And the rear view. I desoldered the mains cable so that I could rotate the transformer up and to the left, remove and replace the bushings underneath and then re-assemble. The photo is with the new black rubber bushings in place. I didn't tighten the screws too tight because they just need to hold the transformer in place without compressing the rubber bushings too much.
And finally here's the old removed bushings - they were as hard as plastic:
I can't really do a check of the humming at the moment because there's too much background noise, but I'll have a listen tonight and provide feedback.
Got a special order!
I've just been fixing a Beo4 that I purchased 'not working' on eBay. Totally dead on arrival and with evidence of battery leakage (as mentioned in the listing), most of which had been cleaned up.
There were two problems: Firstly the little 5.5mm nuts that secure the front face to the PCB were too tight, especially in the middle of the remote alongside the MENU and TEXT buttons. These were so tight that I suspect at least one of the buttons was at permanent send. From experience these need to be finger tight, and you should experiment with the feel of the keyboard before re-assembly. (Although now working, the central remote buttons do still feel a little vague so the dome foil has probably been distorted by being too tight. If I can't live with this I will replace the dome foil.)
Secondly the +ve battery terminal had been corroded by the battery leakage and actually snapped off just upstream of the solder joint. There was insufficient metal showing to re-solder, hence I made a new battery terminal (just the metal piece) out of a brass picture hook, as shown below. This worked very well!
Hello everybody,I just helped an ugly duckling to a new life.
The Beomaster 3300 needed a complete recap.
I also noticed that the top PCB was blackened from the bottom in one place. On the PCB below was a constant voltage source LM340T-5.0 which had apparently become very hot. I replaced it and mounted a heat sink for safety.
After I had assembled everything, I was shocked. The unit did not make a sound. Not even the power LED lit up.The next day I found the fault. The LM340T supplies the processor with the necessary 5V and nothing arrived. Due to the heat, the conductor path at the output of the LM340T was interrupted, which was not visible to the naked eye. The conductor path was patched and the little guy was back!It's ugly, but now it sounds very good again and is already listening to the Beolink 1000!
Hello,
the Beomaster 3300 has been running in my office for a few days now. He has a good reception and behaves also inconspicuous.One thing is strange though. The two tuning displays always burn quite brightly in stereo mode and show only very slight differences when tuning. To tune a station cleanly you have to switch to mono and then work the tuning indicators very well. They get brighter and darker and when the station is best tuned they burn equally bright. As it should be. You can then switch back to stereo and have a well tuned reception.Is this behavior normal?Or do you have a tip what could be wrong here?Thanks in advance!
Activating Stereo also activates AFC.All normal for this model.
Hello Martin,
thank you for your quick and as usual well-founded answer!
Kind regards,
Wolfgang