beolover: Beogram 8000 (Type 5613): Full Functional Restoration and a First Spin with Earl Klugh and Bob James

This post describes the restoration work done on a Beogram 8000 (Type 5613) that I recently acquired from a customer in Tennessee. The unit arrived well packed in double boxes and no shipping damage occurred.

This shows the final result of my efforts:

Beolovely! This restored Beogram 8000 is available for purchase at the DKaudiolover store.

Lets see how I got to this nice result!...;-):

I extracted it from the packaging and put it on the bench:

Aside from a few scratches on the hood and the usual loose aluminum panels this unit looks pretty good. It has almost perfect aluminum surfaces:

All the double sided tape had completely deteriorated:

I removed the loose parts and put it into service position:

Then I extracted the functional parts and put them on the lazy Susan waiting on my bench:

Then I put some isopropanol drenched paper towel scraps on the deteriorated tape

And put the aluminum panels back with some added weight to enhance the interaction between alcohol and tape and to reduce evaporation:

When doing this, care must be taken to not drip alcohol onto the lower part of the enclosure. The black paint on it dissolves in alcohol! So I stuck the lower part into a garbage bag to protect it. The metal plates under the arms are small enough to directly submerge them in alcohol:

My first step once a Beogram 8000 or 8002 has been setup on my bench is to epoxy the hooks for the leaf springs into place:

This is a very helpful thing to do since it will make it very easy to hook the floating chassis back onto the springs. One also does not loose them while working on the unit!...;-).

After the epoxy hardened, I plugged the unit in and pressed start. The carriage started moving but the platter speed was erratic and way to fast. On the display is showed only "33." or "45.", which is an indicator that the microcontroller is not able to get the platter to rotate at the calibrated speeds.

When the processor measures the correct speed, it shows "33.33" or "45.00". With the Beogram 8000 this behavior usually suggests a delaminated plastic tacho (rotary encoder) disk. This was confirmed after I removed the platter spindle: The film with the black marks had partially delaminated. The new laser cut replacement disk from the DKsoundparts store is shown to the right of the spindle:

It is not very difficult to install the new metal disk. All one has to do is to carefully pry the ring loose that holds the disk in place:

This shows the removed plastic disk, the new replacement and the locking ring:

I stuck the new disk onto the spindle

and then pressed the locking ring onto it:

Next I put the spindle back into the bearing and pushed the rotary encoder sensor back onto the disk:

Then I plugged it back in and pressed start again. It immediately found the correct speed:

All good again in the tacho department!

The next step was to restore the PCBs. I unplugged it from all the connections

and removed the microprocessor can:

I replaced all the electrolytic capacitors. I used a new Beolover part for replacing the large 2200uF can (silver):

This capacitor has a special package that is not produced anymore. It has four pins. This picture shows it after removal together with its replacement:

The three pins on the perimeter are all connected to the negative pole of the capacitor. This feature is used in the circuit board layout of the Beogram 8000 and 8002 since it can be used to bridge traces on the board. This is a valuable feature on single layer boards like that of the Beogram 8000/8002!

The Beolover 4-Pin 2200uF Reservoir Capacitor for Beogram 8000 and 8002 shown next to it on the right uses a round adapter board that 'translates' the standard radial pins of the new capacitor into the 4-pin format needed to fit on the board:

Beolovely! After replacing all the other electrolytics, I also replaced the two added capacitors on the solder side of the board. Original:

And the replacements:

After re-soldering all the board headers on the main PCB it was time to focus on the microcontroller PCB inside the metal shield:

There is one important electrolytic capacitor inside that definitely should be replaced when restoring a Beogram 8000 or 8002. It is the decoupling capacitor that stabilizes the power supply of the controller from the noise in the power rails coming from the other components of the electronic system (most notably the motors). If this capacitor is out of spec there is a high possibility of erratic behavior of the controller. Unfortunately, it is a bit of a pain to replace it. I removed the top lid of the shielding can:

After pulling up the small board they added the (golden) capacitor can be accessed:

Here a more magnified shot:

The fun part is that the left solder point needs to be soldered from the top and that there are two wires attached to the pins! I also removed the bottom of the can. The solder point of the capacitor to the right is obscured by a shielded wire:

It is best to remove this wire for the replacement of the capacitor. Since it is soldered in from the top on the side with the blue wire attached, it is best to unsolder the other side, then pull that side up and rotate the capacitor until the other lead breaks off:

This gives access to the solder point and the remnant of the lead can be removed. The new capacitor can be soldered in by leaving the lead a bit longer than usual, so it can be bent to the side for access for the soldering tip. This shows the new capacitor in place with the red and blue wires re-attached:

After this was done, I added a little bit of shrink tubing to the single connector on the other end of the white shielded wire:

This wire has a tendency to break off and the shrink keeps it from doing it. Then I re-installed the processor assembly on the main board. This shows it together with the removed parts:

There are two more capacitors that need to be replaced. They are directly soldered to the 5V and 15V regulators that are fixed directly to the bottom of the enclosure for heat dissipation:

This shows them replaced:

I also added a (red) switch to the output connector assembly that allows connecting system and signal grounds in case there is a hum in the audio signal:

This assembly also contains the output muting relay. It is under the clamped on metal shield inside the assembly:

After pulling off the shield the relay is revealed:

I replaced it with a Beolover Output Relay for Beogram 8000:

This concluded my work on the electronic system of the Beogram (or so I thought!...see below...;-) and I focused on the mechanical restoration tasks. As usual the parts responsible for the translation of the carriage were gunked up with old hardened lubricants:

This shows the liberated carriage after removing the parts:

With the carriage in this upright position it is the perfect moment for adjusting the arms parallelism since the screw can only be accessed when the carriage is removed. Using a screwdriver

I adjusted the screw until the arms were parallel:

After cleaning the rods on which the carriage travels I coated them with Tactikel NST, a nanoparticle based coating that makes metal surfaces very slippery. The purpose is to reduce the friction of the carriage to a minimum to get the smoothest possible travel behavior. After coating the rods they needed to 'cure' for 2 hrs. I use a jar to minimize the area where they touch something while this process is happening:

After two hours the excess material can be removed with a soft cloth. In the meantime the other parts came back from the ultrasonic cleaner:

I reassembled the mechanism:

and also installed a new EPDM carriage belt:

Beoshiny! Next I focused on replacing the light bulb in the assembly that enables a continuously variable carriage speed when using the << and >> buttons on the keypad. The mechanism is in the black box mounted to the backside of the PCB attached to the keypad:

I opened the box up:

This reveals a light bulb in the center and two photoresistors to the left and the right. When the << or >> keys are pressed an aperture is pushed to varying degree in-between the bulb and the resistors. The amount of light making it determines the speed of the carriage. I like to replace the bulb with a LED to make this setup more stable. Bulbs change their output intensity over time which changes the calibration of the mechanism. They also like to break. This bulb was definitely past its prime. It immediately lost a leg when I removed it:

I usually replace these bulbs with a white LED that I treat with some sandpaper to give it a more uniform emission characteristic, similar to an incandescent bulb:

A standard 5mm LED fits perfectly into the space previously occupied by the bulb:

Of course a suitable resistor needs to be put in series to limit the current. The bulb runs at 15V, so a typical value is between ~3.3 and 10kOhm. The actual value depends on the type of LED and the type of photoresistors that are installed. So a bit of experimentation can be necessary. This shows the resistor in place:

It needs to be close to the black assembly. Otherwise it can obstruct the installation of the board under the keypad. The next step was adjusting the control voltages of the released << and >> buttons to 620mV (after the circuit is running for 5 min):

After this I hoped I could adjust the tracking sensor feedback and then enjoy playing first record with it. But I had to realize that the light bulb in the tracking sensor compartment had died. The bulb is in the compartment directly under the arms:

After sliding out the metal cover plate the bulb and the photoresistor can be accessed:

I made a prototype LED replacement based on the circuit board I use in my tracking sensor LED assembly for Beogram 400x. I wrote a separate post about my process. This shows the final prototype next to the original bulb (which also had a broken off lead):

This shows the LED replacement in action:

and with the cover back on:

Note added in proof: I designed a dedicated LED board with which I replaced the above prototype in this Beogram. See here for a post that details this process.

And then it was finally time to enjoy a record! I selected a nice re-issue of "Serenade to a Soul Sister" by the Horace Silver Quintet with Stanley Turrentine. This great record was originally recorded on Blue Note in 1968 (BST 82477):

It played very nicely! Wonderful! Time to restore the enclosure!

The alcohol had dissolved the old glue in the meantime and I was able to remove the degraded tape that held the aluminum panels in place:

Here a photo of the cleaned attachment area of the smaller panel:

I usually use 4-40 washers and dabs of epoxy for glueing the larger aluminum plate in place:

While the epoxy cures the panel needs to be held down:

Carpenter clamps work nicely for the three accessible corners, but for the fourth a heavy weight needs to be employed! I usually use a mallet with a foam pad to protect the aluminum surface.

I also glued the metal shield back to the metal cover under the arms:

Another item that is usually necessary is the replacement of the original degraded rubber bumpers on the front corners of the hood. They give it a nice solid 'plonk' when it descends onto the aluminum surface by its own weight. I use a 2mm drill bit to get the old rubber remnants out of the orifices in the hood:

Then I superglued pieces of a 2mm EPDM O-ring into the orifices:

After the glue had hardened, I cut them to 1mm length:

After this I put the components back into the enclosure and plugged everything together.

Then it was time to enjoy this lovely restored Beogram 8000 with a nice record! I selected a recent favorite, the second collaboration between Bob James and Earl Klugh "Two Of A Kind", which they recorded in 1982 on Capitol Records (SMAS 12244 - gatefold cover). This album is a perfect contemporary for this lovely Beogram 8000, which became available also in 1982! Here a couple pictures of the Beogram in action: