[Pindsen]

Okay, to finish up my own thread 🙂 my conclusion is now that there did not exist a proper connection between aluminium part and amplifier despite being screwed together. I noticed that the screws are some kind of black CED coated, and by working the screws back and forth several times the hum disappeared and the speaker now works as it should.

Location: Denmark

[Pindsen]

I have discovered that if the outer aluminium part is being touched it increases the hum. My assumption is that the aluminium part is/or should be “grounded” to the amplifier via the six screws?

Another discovery is that when doing a short circuit of the RCA input the noise in the RCA switch selection lowers to nearly nothing.

I have tried to see if the internal cabling is correct, and it seems like. It though wonders me why the audio cable runs directly under the transformer.

Location: Denmark

[Pindsen]

No I tried without any audio cable because that to me should be a good starting point where I would expect red LED and total silence.

If I apply a powerlink cable it is more or less the same with green LED and around same hum, but if I apply an RCA cable the hum gets a lot higher.

Location: Denmark

[Pindsen]

Hi Steve,

There are from time to time dicussions about what is going on in all the “old” B&O factory buildings.
To my knowledge the Farm has been “taken back” by B&O after they at first tried to sell it and then later rentet it to the Struer municipality, maybe B&O is going to use it again?
We know that Factory no. 5 is the aluminium production, but after your visit do you then  know what is going on in factory no. 3 and 4.

I don’t know if factory no. 2 is used by B&O or part of Sound Hub as Factory no.1?

Personally I think it could be cool if B&O started up production again in Struer (Made in Denmark). We hear here in DK that more and more companies take back production from especially China but also other countries, maybe B&O has similar plans?

/Pindsen

Location: Denmark

[Pindsen]

Hi Steve,
Very good videos from your visit at B&O and the collectors you met.

Did you do a recorded interview with Kristian Tear that will be public or can you tell more about what you talked with him about?

/Pindsen

Location: Denmark

[Pindsen]

I have replaced the SE8002 with a BC141-10 and it works fine. I had then 62V at BP testpoint and trimmed it to approx. 60V.
Only downside now is that it gives a high pop in the speakers when they are coupled in.

/Pindsen

Location: Denmark

[Pindsen]

Hi,
If you are nervous about your cover then this is maybe not an option, but I have heard that cleaning cables and fabric in the dishwasher on a soft program can do the trick. I have myself tried with cables but never with fabric.

/Pindsen

Location: Denmark

[Pindsen]

Hi again.
Thanx for helping. You where right regarding using the phono plugs, then there are sound using the Tuner and AUX input.

Regarding the power supply issue the 33V part is OK but the 60V is wrong. I have found that component 471 (SE8002) is shorted between B-C (4 ohm). I am not able to find a SE8002 but according to this old post a 2N2102 should do the job:
https://archivedforum.beoworld.org/forums/p/40097/335005.aspx#335005

/Pindsen

Location: Denmark

[Pindsen]

Hi,
Yes of cause, now I get it 🙂
Then I have three more questions:

1. When I apply a line signal to TAPE I have sound in speakers, but when I apply the same line signal to either the TUNER or AUX there are no sound. I have tried to follow the schematic but it just a lot of switches – any idea?
2. There are adjust knobs in the bottom and also High/Low switches – It is mentioned in the service manual but I can’t find how to adjust the knobs, is it just by ear? – any idea?
3. I have low light in the bulbs and at test point BP I only measure 25,5V (60V is expected). I have tried to turn the potentiometer 457 but no change, it is steady at 25,5V. Before moving on I would to hear any ideas?

   /Pindsen

Location: Denmark

[Author]

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