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
Thanks Soren.......I really must put a DBT together next time I undertake a project, Its unpleasant powering up for the first time when you know there is a possibility of crisping something and rendering all your work useless. Thing is I'm starting to become awash with B&O amplifiers.......bit like the broomsticks in Micky Mouse's the Sorcerers Apprentice ;¬)
Hi , reading your restoration with great interest, and finishing up my own 4400, looks good sofar...but this bumblebee is cracked and i can't figure out which one it is to replace it correctly
Color decoding give me 100nF (0.1uF) but the schema seems to indicate 10nF so im a bit puzzled.... Have you replaced yours, and if so with what?
Possibly 0C6 from the partslist?
Many thanks
//g
BM 2000 *1974, 2x BM 1200, BM 1001, BG 1200, BG CD X, BC9500,BM3300,Bcord 3300, BG CD3300, Beovox Cona, Beovox CX100, Beovox 1200, Beovox RL60.2
Hi Garten
I have checked my 4400 and this capacitor is exactly the same on my unit as yours, I will post a pic later this evening, my feeling is to go with the component we know and replace like for like......I'm not convinced that the circuit diagrams accurately reflect the correct components across all variations of each system. I have a capacitor on my power supply that does not appear in the circuit diagram.
Craig
It's a 100nF capacitor and it looks absoutely fine.It's quite common to see these "tropical fish" polyester capacitors develop tiny cracks where the leads are soldered internally.It has no influence on the reliability of the capacitor.I would gladly leave it there.
As Craig says, you can find countless inconsistencies.As a general handrule, it's best to trust what's in the Beomaster rather than what's in the manual.
Martin
chartz:This Beomaster is my favourite B&O receiver, in use every day chez Jacques. Very nice!
The work that you have done is absolutely amazing. AMAZING! I am completely impressed.
The part I don't really "get" is the remarkable fondness for one amplifier over another. (Sorry Jacques and Soren)
Perhaps it is because I have a crippled Beomaster 4400..... which I use virtually every day as well, but I would be hard-pressed to say that it is any "better" than either my Beomaster 2400 or Beomaster 4500.(They get daily use as well.)
True, if you are powering large inefficient speakers the Beomaster 4400 has an advantage. However listening at fairly high volume (guilty) all three perform to the highest standards.
Anyway, my "confused" remark does not in any way take away from the wonderful transformation you have performed.
I clean, I polish, I tinker, but I don't remotely have the ability to achieve what you guys do.
Congratulations on your Beomaster 4400 restoration!
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
Thanks all. I will leave the capacitor alone.... Had time to start it up , all went fine, voltage across resistors check and adjusted to 5.6 (half by measuring one only, like shown on forum...and beolovers blogg), but i might have probed incorrectly to adjust tuning voltage diling to the far left.., 4,6v but i had a hard time identifying the white/gray cable to probe against, so im usure im right.... if anyone has the time and can muster the energy, i would be grateful if they can have a snap of their innards and point me to that probe point on pushbutton switch PCB 6.
I also somehow zapped a tuning indicator bulb.. don't ask how...looked liked it has been previously repairded by getting daisychained together... I'll get a pic for you..im not sure they ever worked properly, both had the same intenisty :=) possibly the previous guy though it looked better then both never working...don't know,.. Dillen you got a message, hoping you have a few spare bulbs ..6v 80mA?
Craig,
Well done!
Just to reply to your question about the 0.5 ohm indicated resistance of the 0R18 Bias resistor.
Most DMM's, including Fluke (which I have also), are incapable of low ohm resolution.
You need a Milli-ohm Meter (expensive) or a EVB ESR meter (inexpensive) which doubles as a capacitor checker AND a Low-ohms meter. It's very accurate for the purposes of checking Bias resistors.
I buy all my Bias resistors from a UK website HiFiCollective. They stock the original Mills resistors - specifically designed for quiescent current, and they still have lots of old stock. I use the 5Watt units.
Recently Mills was bought out by Vishay, and production was moved to Mexico. Nothing against Mexico (soren ;-), but as long as I can get the original parts before the bean counters started doing heaven-knows-what with the production lines, I'll stick with the NOS pieces.
I haven't finished my BM4400 restoration yet, as I am completely overloaded with customer work, but as soon as it's done, I'll be posting details. There is no doubt - it is a massive undertaking.
Menahem
Cheers Menahem
I have used HiFiCollective for supplying capacitors in the past, didnt know about the Bias resistors though. Looking on ebay there is a bewildering number of EVB/ESR meters available at almost any price your willing to pay, I will need to research further to ensure I buy the optimum unit.
EVB is the manufacturer in Portugal. I do not believe that the owner, Vito, uses Ebay to peddle his products.
He sells direct only from the factory.
Being in the EU, there is no tax, and his after-sales service is impeccable.
EVB (Portugal) and Anatech (USA) are the ONLY 2 licensees of the original DickSmith ESR patent.
Email him and let him know that I referred you.
I wouldn't touch any of the Chinese ESR units.
A cheap troubleshooting piece of kit which doesn't function accurately, is not worth any money at all.