Beogram 4000 and also BG8002

[hcraig244]

After a fairly long hiatus I have undertaken to do some restoration work on one BG4000 (my favourite) and 3 0ff BG8002…units I have no previous experience with….so this is going to be fun!

 

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[hcraig244]

The BG4000 looks in very good condition internally with no signs of previous repairs…always a good sign

not sure about the quality of that image, but all looks well inside

Carriage drive belt is a bit out of alignment, not a problem.

[hcraig244]

However the dust cover looks like some work has been carried out, this will require some attention…

The wood trim looks in good shape with all corners still sharp and clean

Overall the unit looks in good shape mechanically, and mostly cosmetically too.

A test run will determine if there are any issues functionally..

[hcraig244]

Powered up via the variac and all is well, no smell of burning or sudden cracking of blowing fuses….hooked up to a BM4400

[hcraig244]

With no fault finding/repairs required, good news, a kit to include all the usual caps and trimmers along with drive belts will be ordered from Dillen and a straight forward replacement carried out…..the trim will need attention, it has been repaired once before but needs a little more work

 

 

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[hcraig244]

I’m thinking all further pics will need to be via attachments as the definition is superior….next up for inspection the first of the BG8002 decks

 

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[hcraig244]

I have been awaiting delivery of platters and cartridges for these three decks in order to determine status prior to ordering the required parts from Dillen, didnt want to order kits and then discover additional parts where required due to an unknown fault…saves shipping costs to buy everything in one go ;¬)

Platters and cartridges arrived yesterday so will be inspecting the first one today

[hcraig244]

First one up fitted with platter and cartridge, powered up via variac and came up nicely…nothing untoward so went ahead and connected up to a BM6000 and although the sound came through on both channels there is an overriding hum that sounds very like a grounding issue…..tried with a BM3000 and also a Beolab5000 and the hum remains…..

 

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[hcraig244]

Second BG8002 up for testing complete with platter and cartridge….all visual inspected fine, powered up and still looking good….however the tone arm refused to drop when asked….tried a couple of times to no avail, interestingly the hum/buss that I suspect is a grounding thing presents itself when the tone arm is asked to drop….I’m seeing a trend here

 

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[hcraig244]

On checking the output cable provided by the owner i see its a 5 pin DIN to phone plugs….the DIN socket on the deck is a 7 pin…the service manual suggests a number of earth/ground connections are not getting picked up by the amps I am connecting too….

[hcraig244]

3rd BG8002 on the bench…powers up fine and all lights illuminate when play is pressed, platter spins and tone are begins to move to the drop area when it stops short and stays there, wont stop and needs to be moved back by the reverse button at which point all goes back to standby….dont know if the buzz/hum is present?

 

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[hcraig244]

So there we have the project in summary:

1 BG4000 in working order with some work on the dust cover trim

1 BG8002 in working order with a suspected ground hum/buzz going on

1 BG8002 mostly in working order, the buzz/hum is present here too, with the exception no tone arm drop, I’m suspecting something mechanical,

1 BG8002 with operational issues around the tone arm movement and possibly drop..the tone arm cover is loose so im suspecting it may have been looked at in the past.

As always any suggestions will be welcomed along with encouragement of course ;¬)

 

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[beogram8002]

What a cracking workbench that is Craig, 4 x Beograms laid out ready to be sorted and back to playing nicely again 🙂

This is what I got from AI on google  –   “When a Beogram 8002 tonearm fails to drop on a record, it usually stems from a mechanical jam in the arm lowering assembly, a worn-out tangential drive belt, or an electronic fault preventing the lowering solenoid from triggering.

The 8002 tangential tracking system uses an opto-electronic sensor mechanism to detect the record edge and determine when to drop the stylus. To troubleshoot and fix the issue, check these key areas:

Check the Solenoid & Electronics: The arm lowering mechanism is activated by an electronic solenoid. First, ensure a cartridge is correctly installed and the tracking force is set. If the arm moves over but refuses to drop, the solenoid might be stuck or the electronic control circuit (and its associated capacitors) may have failed.

Inspect the Tonearm Drive Belt:   The linear-tracking arm relies on a rubber drive belt to pull it across the record. If this belt is stretched, slipping, or has turned into sticky goo, the arm assembly cannot pull itself into the correct position to drop.

The tonearm lift bar must be resting freely in the “V-channel” of the vertical adjustment screw. If the turntable was recently moved, the tonearm assembly can shift and cause the lift bar to stick to the side of the V-channel instead of dropping. Additionally, the tonearm must remain perfectly parallel to the stationary sensor arm (a gap of exactly 7.7 mm)

• This reply was modified 2 weeks, 6 days ago by beogram8002.
• This reply was modified 2 weeks, 6 days ago by beogram8002.

Location: London UK

[Mark-sf]

The extra pins in the DIN connector are for a datalink connection allowing the remote control from the receiver to control the turntable. Those pins can be unscrewed from the Beogram ouput dim. If there are no holes for them, likely the cable has been changed and perhaps grounded incorrectly. Pin 2 is the audio ground and should have continuity to the DIN connector shield and the chassis of the 8002.

[hcraig244]

Mark

Thank you for your response to the above issues, I’m confident your correct in your assessment of the suitability of the existing cable. See below Dillens advice which is very much aligned with yours:

Beogram 8002 requires a double-shielded signal cable (PH).if you are using a cable meant for a Beocord (TP), you will almost certainly get hum.If you are using the correct PH cable, the problem could be a broken ground connection at, or near, the DIN Socket board in the Beogram or inside one end of the cable. At least that would be the first things to check.

I will be contacting Steve of Heavenly Sounds for a price and delivery of a suitable cable over this weekend.

Thanks again for your support

Craig

• This reply was modified 2 weeks, 5 days ago by hcraig244.

[hcraig244]

Beogram 8002

Thank you or your response, you identify some solid starting points to get to the bottom of the issues I have described…I will be addressing the issues for each 8002 in turn, probably starting with the one whose tone arm moves to the correct position but refuses to drop, as you suggest I’m hoping for a mechanical problem…I do hear what I believe to be the solenoid  clicking in prior to the tone arm doing nothing….with the exception of the grounding hum I do have a fully functioning set which is always useful for comparison checks.

Regards Craig

 

[hcraig244]

Ok…..the unit with the tone arm that doesn’t drop first up! removed the dust cover and put the unit into service position

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[hcraig244]

This done pressed play, and following a look at the circuit diagram, located the connections for the solenoid responsible for lowering the tone arm….waited until the arm moved to the drop position, I can hear what I think is  a relay energising, will look further into that, and took a measurement at the solenoid coil connections…. nothing.

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[hcraig244]

Circuit diagram tells me that this coil is fed from pins 1&7 of P3…..white and black, repeated the test and on hearing the click described above I measured 5.0 vdc at the connections to the flexi strip…

 

• This reply was modified 2 weeks, 5 days ago by hcraig244.

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[hcraig244]

Looks like I’m losing my 5.0v to the solenoid coil somewhere along the flexi strip….

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