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 haven't seen bad filter caps in this model yet and I would gladly leave the original caps inthere unless physically damaged or leaking (I haven't seen that yet either).If you absolutely MUST replace them, see if you can find some good quality caps with thesame specs as the originals - and preferably also the same physical size - the latter couldprove difficult.You could choose to up the voltage rating a little, maybe to 63V (no higher) but there's really noneed for it and, unless you buy the REALLY tough stuff, there's a good chance the original caps willoutlive whatever modern caps you would fit instead.As said, don't replace components just for the sake of replacing them, leave them unless youabsolutely MUST do something.
Oh, and please don't use "10k" for capacitor ratings.k is for kilo. 10k would be 10 kilofarad (a capacitor the size of a mobilehome) and a factor 1.000.000 off.10.000uF or 10mF (mF = milifarad) or 0.01F would be correct.
Martin
Thanks Dillen. Filter caps look fine. I recapped tuner and preamp board including the mute relay. Tested it last nite. That relay made a huge difference for volume control. It sounds great. I did notice that one of the nine 22uf bipolar caps was a Elna 22uf polarized cap. It was also in the small bag. Now I did count 10 bipolar caps on the preamp/mute board. So I still have two 22uf original bipolar caps left to replace. I went ahead and placed a order for what looked like exact replacements. I musst say I am impressed with this B&O equipment. The 80.2 speaker recap went well. Now I just need to get the other speaker from the original owner.
I have a couple questions. Can normal heat sink compound be used on the fan blower circuit? I have some by GC Electronics(type 44) that I use on transistors. Also I would like to possibly replace all the heat sink film for transistors to heat sink. Actually only one of the films looked sketch. It was two thin pieces. If I decide to replace the films what would be a good material that I could possibly source from local electronics store? Thanks in advance. The recap is going great!
Well this post will be short and sweet as the one I typed up five min ago didn't post lol. Can normal heat sink compound be used on the fan blower circuit. I removed the amp heatsink to apply new paste to all components. I do have good paste for transistors, also what would be a good alternative heat sink film for the transistors? One of mine was made up of two thin sheets. The others look ok to me but I was hoping for someone more knowledgeable to answer. I do have a good local electronics store five minutes away. Thanks. The recap is going great and I can't wait to finish and enjoy this receiver.
Yes, normal heatsink compound for everything on the heatsink, including the small NTC (or PTC, I don't remember) resistor.I prefer the old mica sheets rather than the newer and thicker grey silicone-like insulator sheets.
Thank you so much for all your help Dillen! I am a bit nervous about reassembling the heat sink (lining up everything without making a white paste mess). I just talked myself out of using existing mica pieces. One of them came apart and now have two thin pieces. Just had to remind myself to take it slow and prevent costly mistakes down the road...like destroying those nice Philips Darlingtons. If the local Ralph's electronics store doesn't stock any then I will have them order some or source some from eBay. Recapped the fan control board earlier now I'm about to pull out the processor board and recap it. Other than the two bipolars caps for the preamp...that will complete the recap.
Help Dillen! I am on the last cap. The 33u 25v blue axial cap that goes on processor board. I am confused about polarity orientation. The black bands have been neg so far but this one has a black band on one side but when I check it with dmm the positive lead on black band side and negative lead on other side gives me correct polarity. I do understand this to be a correct way to check polarity. I don't want any problems this late in the game lol. Thanks again
Where one lead enters the caps housing, it goes through black insulation. That's the positive lead.The other lead is attached directly to the metal of the caps housing, That's the negative lead. The negative lead is typically alsomarked with a ring around the cap near the negative end.
That's a good simple way to identify cap polarity. I believe I knew that at one point In my life but like many things I've forgotten. Here is my BM 5000 update...about to reassemble the heatsink to amp board. Taking my time with it. Might be able to power it up tonight if I'm not to tired.
Well alright alright...it lives! Heat sink assembly wasn't as bad as I thought. Plugged it into mains and red led came on...relief! Plugged in antenna and headphones and got music. So tomorrow I will look into adjusting idle current. I tried my best to match resistance of existing trim pots to new pots, might need some assistance with setting the idle current because I've looked through the SM several times and haven't yet seen the section for adjustments.
Ok I found the adjustment info in section 5... The very first page lol. All I did was checked the power supply 5v on conn 23 on module #4 then adjusted left and right channels to around 10.94mv. Wasn't hard. Am I close enough?
Close enough.Well done !
Thanks Dillen! Just tested left and right channels with the one S80.2 speaker. Sounds good. Need some "D" batts for the remote so I can adjust bass an treble. I also tested the onboard fan with a heat gun...it's so quiet. Going save the receiver to the closet as I am I going offshore(work) tomorrow for a couple days. All that's left is the two bipolar caps on the preamp board and those are scheduled to be here tomorrow. Once it's all done this beomaster is going to reside on my bedside table. It won't get a lot of use in there but I could be wrong lol. Oh, one more major hurdle...getting the other S80.2 speaker.
Good news the caps showed up in mail a day early. Soldered them in earlier and finally buttoned this receiver up. The cover haven't been on since a couple months ago. Took a few min to figure out how to reinstall the cover. Oh I did retest trim pots and audio to speaker on both channels. All is well. Very enjoyable project and the modular design with connectors is just a pleasure to work on. Very impressed with B&O design!