Bang & Olufsen BeoCenter 5000 - part 2. I think it's time to get back to basics.
ฝัง
- เผยแพร่เมื่อ 21 ส.ค. 2024
- My usual technique in restorations is to work backwards from the power supply. So I usually do the power supply, the power amp, the preamp, and the various sources, in that order.
I started this one in a rather unorthodox fashion, but decided that I'd stand a much better chance of success if I reverted to my tried and tested method. So, here goes ...
Power supply, and power amplifier.
Hope you enjoy it.
This video has edited English subtitles, to allow for better translation to multiple languages on the desktop App.
You can now support the channel:
/ mcaldeira paypal.me/maca...
#tuberadios #antiqueradio #radiorestoration
_____________________________________________________________
DIY TEST GEAR: The title says it all:
• Zener Diode Tester - P...
RESTORATION BUILDING BLOCKS: A series of videos showing detailed steps used the restoration process of tube equipment:
• How to safely check th...
HowTo's: Various videos on some simple techniques and projects:
• Extend tube radio FM b...
See also playlists on some other completed restoration projects.
PHILIPS BX750A:
• Philips BX750A tube ra...
TELEFUNKEN OPUS 2114:
• Telefunken Opus 2114 s...
SABA UW-175-Z 3D:
• Saba UW 175-Z 3D tube ...
GRUNDIG 1070:
• Grundig 1070 tube radi...
SCHAUB-LORENZ GOLDY 58 type 3020:
• Schaub-Lorenz Goldy 58...
BUSH VHF64:
• Bush VHF64 tube radio ...
GRUNDIG 3060A:
• Grundig 3060a tube rad...
TELEFUNKEN OPERETTE 8:
• Telefunken Operette 8 ...
GRAETZ SUPER 171W:
• Graetz Super 171W tube...
LOEWE-OPTA MAGNET 3737W:
• Loewe-Opta Magnet 3737...
BRAUN ATELIER 3:
• Braun Atelier 3
LOEWE-OPTA TRUXA STEREO 4741W:
• Loewe-Opta Truxa Stere...
GRAETZ COMEDIA 616:
• Graetz Comedia 616 tub...
SABA FREIBURG W2:
• Saba Freiburg W2 (WII)...
GRAETZ MUSICA 4R417:
• Graetz Musica 4R417 re...
You may also be interested in ...
CAPACITOR LEAKAGE TESTER:
• Capacitor leakage test...
![เบิ้ล ปทุมราช - สาวสอง ( มีมี่ของอ้าย ) ft. ตาต้า,ต้องเต [OFFICIAL MV]](http://i.ytimg.com/vi/mqlMjnP08XI/mqdefault.jpg)
Going back to basics was definitely a good idea. Seeing some of it working at least gives some hope for it :).
Looking forward to seeing this progress.
Little steps :)
Hi very interesting faults finding video of the bang olufsen amplifier you are professional master a d when are you going to make part 3 ? It will wi great and we all can learn from you thank you
Sam
Unfortunately this project was shelved, as I had said it might be.
Eally enjoy your thoughtful and complete troubleshooting. You projects have really improved my ability to read schematics (still not where I want to be but much improved!). Great video as always.
Thanks
A very interesting repair you have taken on Manuel...
Indeed :-)
You're very brave trying to fix this 5000 centre. It does look easier to service than other B&O stable receivers, however. It's great that you've made such good progress in such short time. You can't give up on this now! I understand that your aim is to restore full original functionality? Even without the microprocessor and associated board working, it should be possible in theory to substitute it's function with rudimentary circuits (if it comes to that) as it is basically serving the purpose of an electronic selector switch? So for me there is still value in restoring the rest of the receiver/centre back to working condition anyway.
That is the thinking that I’m inclined towards at this stage. We’ll see how it goes.
@@electronicsoldandnew You probably know about it already but it doesn't hurt to post the link to this repair document for the 5000 specifically that I just came across :
www.condoraudio.com/wp-content/uploads/Projects/BeoMaster-5000-Receiver-Restoration-Repair.pdf
On the same site there are a couple more B&O and other devices repair notes.
I have a similar project in my backlog, working on a Tek 2465A scope I put together a mainboard bus analyzer to do numerous tasks, primarily map out the address space and then read out the Calibration RAM. I used a Arduino board to simulate all of the data, address and control lines. I need to get back to that at some point...
I consider the Arduino IDE and framework to be a bit of a toy, but its handy for rapidly throwing together something like this. Lots of I/O. And importantly the older ATMega microcontrollers are cheap, available and 5V or 5V compatible, old kit like this radio does not like 3.3V.
Incidentally I see some efforts at emulating ICs and other things with FPGAs; they are all lower voltage these days as well. For them, 3.3V is "old school" and modern FPGA cores are running less than a volt.
If you cannot get OEM parts then an ATMega, TI MSP430 or even a PIC-chip are alternatives if you can suss out the firmware. A 32-bitter would be overkill though...
Cheers,
I’m trying very hard to keep the depth of the rabbit hole manageable, because when I get curious, I do tend to get carried away. Don’t tempt me :)
@@electronicsoldandnew - Hrm yes, sometimes the temptation to "monkey about with it" can be _irresistible_ ... I shall put my pitchfork and horns away then :D
Cheers,
@@EngineeringVignettes lots of people would be interested in this (not just for the 465 owners). It would make for a great video (or a dedicated website/github project).
@@Stelios.Posantzis - I was thinking of covering it in a future engineering vignette on my channel... working through some audio issues at the moment and there is a backlog of other stuff to do...
Thanks,
@@EngineeringVignettes I'll be sure to watch out for it.
Excellent! Thank you.
Pleasure
Just to add to this... I had a Beomaster 5000 that ended up having a failed main microprocessor. No idea how or why, I bought it that way. So, apparently, they DO go bad!
Unfortunately yes
Manuel, you certainly have a brainteaser with this project. You’ll need to work an American five to unwind.
Joking aside again your use of schematics showing us your troubleshooting process is entertaining
thanks
Yes, an all American five, with live chassis, could well keep me in a totally relaxed state after this one 😊
Hope the needle and cartridge are in good condition, very expensive to replace. MMC-20E over £300.
I know. I’m anxious to test that too.
@@electronicsoldandnew If there's problems with the cartridge, needle, contact Sound-smith, they rebuild B&O cartridges:
www.sound-smith.com/services/cartridge-rebuilding-retipping
I had similar case of "standby-reset" circuit failure in my Braun R4 (receiver with digital control built on 4-bit Hitachi/Sampo processor - unobtanium, programmed with mask process in factory).
I was sure it is completely dead (after connecting the mains plug: strange segments on displays like yours, no clock activity on CPU, no keyboard scan lines active etc.). Dead and deaf, hence the price was attractive....
First thought - to replace the cpu. 150 Eur per board, used, claimed to work. No option for me.
Then after further investigation, I had figured out that, to properly execute reset sequence, two low volt DC power sources needed to be synchronized with certain delay, otherwise CPU would hang on reset on unit power-up.
The first low voltage supply was the standby 6V for CPU board itself, which also generated the delayed RESET signal. It should have come few hundred milliseconds earlier than the other 15 volt auxiliary standby supply, which was used to drive the NMI signal. Those two (NMI and RESET) had to be synced according to datasheet, otherwise the CPU was held frozen, not even reacting to forced reset.
It took me three days to solve it, the culprit was one 1uF capacitor not delaying the 15 volt supply enough and two 1n4148 diodes pulling the signals below specs.
Since then, I already brought to life three different CPU boards (I know, I must be crazy enough with this Braun R4 receiver, to buy 3 of them broken).
I keep fingers for your fix of the BO cpu board, without replacing it. The probability of failure of those industrial processors is very low. I hope you would be successful as always. Do not give up!
Inspiration is most welcome. Thanks. I also believe that the probability of the cpu being dead is rather small, so I’ll keep enjoying the experience of moving though this set one stage at a time.
Please upload the next episode. I need a fix.
That sounds bad :)
Hello my friend, I’m looking about on internet for help with my Pioneer A300 amplifier. I have no sound at all from the right speaker outlet, I have just bought it off eBay and I really do want to keep it, get it working. Do you think you might be able to help me?
It would be really appreciated.
Thank you
James
Sorry James. I only do my own hobby projects and hope that seeing them can help someone gain some ideas for their own repairs. I don’t do this professionally.
Isn't the 8048 not WITH ROM on board? How can you change then the chip? Or do you get the programmed one?
Or am i totally wrong?
Yes, it has to be bought with the original program on it, or it’s worthless.