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Deciding the way forward was to replace the cloudy lens with the not so cloudy lens on the one I had just installed I set about dismantling the not so cloudy meter and discovered the internal connection from the + post was loose….tightened it up put it back together and having removed the newly extended + wire I soldered it back in place…..and yes everything worked fine!……spent a couple of hours on this

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However I extended the + wire and soldered the cloudy meter in place and ran another test, all worked fine

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The polarity of the meters are opposite, someone has erased the + / – markings from the left hand side meter and marked them up opposite to what they where…….the right hand side meter is the one with the milky lens and still has the + / – markings unchanged,

The negative marking can be seen against the right side post, the meters have different shapes too….change in design down the years I expect.

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Thinking I may have damaged it during cleaning I took it out, looked ok and when I put my multimeter across it to check the moving coil continuity the needle deflected 3/4 up scale, as you would expect from the current from the meter set to ohms. I got out a meter I recently replaced due to severe clouding of the lens to compare….and found this curious thing……

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Started by checking the 240v supply to the transformer…..all good, 32v output to the new rectifier and around 40vdc out of the rectifier. Checked the 20vdc supply and found it was around 29vdc…adjusted the new trimmer I installed and brought it back to 20vdc……checked the voltage to the power ON lamp and that was good too…..so replaced the lamp and of course it illuminated ;¬)

Connected a antenna and adjusted the tuning dial, the stereo lamp flickered as it passed through live broadcasts which was very encouraging…..however the tuning meter stayed hard down throughout.

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This is true Soren….I received this from Frede some time ago:

Craigh,

 

It is actually a ”short list” ?

BC 550B for npn

BC560B for pnp

 

When the Beolab was designed (before 1967) only a few transistors were available is really low noise versions – therefore B&O have chosen a number of different types of coarse also being able to be used and meeting the actual voltage level. But I have for many years used the above type in the pre-amplifiers.

And I am using the transistors type B because higher gain in classic electronics design is not a good idea (this is my opinion ?)

B U T — for the power amplifier and the power supply – I only use the original RCA types !!!

For the output power transistors and psu transistors — I am only using the original Motorola or RCA (there are to many “fake” 2N3055 out there).

When I am writing the original it is actually the original because I re-use these transistors from Beolab 5000 which is scrapped.

 

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Removed the link and cleaned up the fuseholder…new fuses installed. Gingerly applied power from the variac up to 220v……and nothing happened, not necessarily a bad thing…there was no smoke or sudden popping of new fuses…..so a little fault finding exercise required….as for now a glass of wine is called for

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Thought I would check the fuses out too before powering up…..this is what I found.

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Finished with the replacement of trimmers and capacitors, all except the channel seperation trimmer…thought I would wait until the unit is up and running before playing around with a replacement for that one.

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And made a start on the trimers……

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New feet arrived in the post…….drilled the old ones out and fixed these with bolts.

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Phil

As I recall I replaced the zener diode 2D9 and the problem pesisted, I then replaced the two diodes 2D10 and 2D8 and still had an issue, I put off replacing the zener diode 0D2 because it was difficult to get at….its hidden away off PCB2 and bracketed against the front end shield box PC1, eventually I had no choice but to do so….and that solved the problem, I cant remember if I replaced 2TR8 or not….the post will be somewhere in the archived forum 2012-2022 along with pictures if you care to try and track it down…..it may help, I would recommend changing 2TR8 seeing as your going to replace the diodes…….good luck I have had lots of fun with the 6000 type 2702 amps.

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Quality…….

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Not perfect…..but I’m happy with the result…..

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disconnected and removed the tuning meter, front lens is a little cloudy from too much UV and some debris has got between the two halfs of the assembly….making it look unkept. Cant do a lot about the cloudy lens…I have tried in the past to no avail….but I can clean away the debris……..

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This was interesting….on removing the front panel for shipping to Frede I discovered a wad of folded paper wedged between the panel and the chassis……..cant imagine what it was doing there?

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And I have now discovered the basis for the “restored by seller” claim on ebay……

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This is what was living beneath the bottom cover…….

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Side panels have also had a clean up and a coat of primer applied…..

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Cabinet top veneer finished, shame to stain it actually….I quite like the iroko wood grain, but will have to match the Beolab or it will look odd.

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