Beomaster 8000 Fault

8 replies

Offline

dahiyas

Bronze

Posted April 19, 2025 at 06:43 GMT

Hi,

I added another BM8000 to my collection. I powered it up with a DBT. I get standby dot. Press the standby button and the bulb goes bright and I hear the clicking of relays and unit goes back to standby. I disconnected the output PCBs and tried again and same result. (also checked all the output transistors and they are ok).

I disconnected P51 on the power PCB and the system comes up and display lights up. So looks like there is something wrong with the power supply section that is activating the fault switch ?

Any guidance on what I should be looking for ?

Thanks !!

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Dillen

BronzeModeratorFounder

12777 posts

Posted April 19, 2025 at 10:27 GMT

#1669548

Beomaster 8000 has a huge rush-in current when powering up.
Your lamp will eat most of the voltage the Beomaster needs to start up properly, and the surge will trigger the standby for safety.
Use a variac instead.

Martin

Offline

dahiyas

Bronze

186 posts

Posted April 19, 2025 at 19:10 GMT

#1669554

Thanks Martin. Unfortunately I don't have a Variac 😐. On my list to get at some point. I do have a voltage protector device that allows me to set Voltage and Current limits. Can I use that instead ?

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dahiyas

Bronze

186 posts

Posted April 22, 2025 at 04:06 GMT

#1669606

I switched on the system with just one output pcb connected as step 1 and once confirmed all was good I connected the second pcb. And everything works. This was my fourth BM8000 restoration. I remember my first one had taken nearly 2-3 months with all kinds of issues (stuck in standby, microprocessor pcb via's, prescaler issues etc). The fourth one just took 5-6 hours.

A big thank you to Martin and John (Sonovar) and others on the forum who have documented their issues/fixes.

Next up - Beomaster 5000 quad (my first one). Project started last summer. Dismantled the whole thing, recapped, bulbs changed. Now I need to put it all back somehow....

BM8000 and BM5000 are on the opposite ends for serviceability !!

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Peter

Gold

10830 posts

Posted April 23, 2025 at 09:03 GMT

#1669614

I take it you mean the 6000! The one that looks like the display for the medical beds in Star Trek - fantastic machine - manages to look space age but uses moving ribbons instead of LEDs. Can't remember what I did with mine! The matching cassette deck in possibly the most unreliable device I ever had! There is a video on Mend It Mark (Youtube ) of him fixing one - respect! The BM6000 is a fascinating bit of kit though the 4400 outperforms it. However the looks are wonderful - pretty sure I scanned the service manual for Beoworld a few years ago. Best of luck with the reassembly.

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hcraig244

Silver

2539 posts

Posted April 23, 2025 at 12:34 GMT

#1669616

Peter

You gave it to me several years ago for replacing the 33/45 rpm relay in your BG6000....or was it your BG4001 (with the black facia) i'm taking good care of it 😁

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dahiyas

Bronze

186 posts

Posted April 24, 2025 at 02:44 GMT
Edited April 24, 2025 at 02:46 GMT

#1669620

Thanks Peter. Yesss, the 6000 !! I have the Beocord 5000 also and completed the restore of that too. The mechanism was pretty painful to say the least. And the sound was not at all impressive. Maybe it needs some calibration but I don't have the tools for it.

But the 6000 was bought for its looks. College kid had it up on craigslist for $600 (for parts) and my $150 offer was rejected promptly. But about 6 months later he sent me a message saying I could have it for $150. I dismantled the whole thing, all wires desoldered etc. Recapping done, gears lubricated. Now the big challenge is putting it all back together and setting trimmers etc before everything goes in the chassis. Maybe a project for the next long weekend.

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hcraig244

Silver

2539 posts

Posted April 24, 2025 at 14:01 GMT

#1669622

That will need to be quite a long weekend.....

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Beomaster 8000 Fault

dahiyas

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