Beogram 8002 (5633): Initial Assessment

I recently received a Beogram 8002 (Type 5633) from a customer in Missouri. It arrived safely packaged in a Beolover shipping container, and no shipping damage occurred. I put it on the bench:

As usual, the aluminum panels had come loose. The hood has some moderate scratching. Also very common. Luckily, this can be fixed. Co-Beolover Beomazed has figured out how to transfer the original trim to a new replacement hood. This is a significant step towards a pristine, like-new look!

Otherwise, this unit is in pretty nice cosmetic condition. The veneer corners are in an unusually good condition:

It also has a platter that looks very good:

Unfortunately, these platters are easily damaged when people try to clean them with alcohol or harsh detergents. It is usually best not to use alcohol on this particular Beogram vintage. The black paint of the enclosure is also easily damaged that way. Water and a mild hand dishwashing detergent, plus a soft cloth or sponge, are usually the best approach.

After this visual inspection, I removed all the technical parts and set them up on my lazy Susan work platform for easy access to all components:

Then I plugged it in and pressed START. It reluctantly moved the carriage over to the LP setdown point and arm lowering was triggered properly. The typical signs of hardened lubricants and/or a worn carriage belt. But after the arm was down, it immediately returned the carriage to the home position. This usually means that the <</>> adjustments are out of whack. 

In summary, I would say this unit is a promising starting point for a full restoration to a like-new condition. Stay tuned for my post about the work that will be done on this unit!

Beogram 6000: Oil Infusion of AC Platter Motor Shaft Bearings

I recently received the AC platter motor of a Beogram 6000 (Type 550x) from a customer in the Netherlands. The motor exhibited knocking noises that could not be adjusted away by reducing the motor voltage. This is usually a sign of dry motor bearings. My remedy for this issue is reinfusing the Oilite motor bearings with synthetic oil under vacuum.

This shows the motor as received:

After a trip to my garage for drilling out the rivets that hold the enclosure together, I disassembled the motor:

It is important to keep the parts on the shaft in their original order and orientation (the washers have an orientation, too!):

Unlike the later DC platter motors, there does not seem to be a straightforward method for removing the shaft bearings from the enclosure halves of the AC motors. Therefore, I simply put the entire enclosure into the oil. This is a bit messy, but it works well. This shows the initial bubbling coming from one of the submerged bearings while the pump labored to pull a vacuum:

A few minutes after the lowest pressure had been reached, the oil had foamed up:

These bearings were pretty thirsty! But I think some of the bubbling up air also comes from pores in the enclosure itself. The infusion process is completed when the bubbling stops. At that point, all the pores are again filled with oil. After two days, the oil became quiet, and I removed the parts from the vacuum chamber. This shows one of the bearings after I cleaned out the oil:

These bearings look pretty similar to the ones found in the later DC motors. They can also adjust their angle to minimize misalignment with the shaft.

I put the motor back together:

If you try this at home, make sure the stacked coils are re-inserted at the correct polarity (purple and green wires need to be on the same side as before, otherwise the motor will run backwards). Since opening these motors requires destroying the threaded rivets that hold the enclosure together, I developed 3D printed plastic parts (red) with integrated M3 nuts for the tilt adjustment screws. Note that without the rivets, the enclosure is mostly held together by the mounting screws after the motor is bolted back into its place in the Beogram. This is not an issue for the operation of the motor, but it needs to be kept in mind when the motor is reinstalled.

Beogram 8000/8002: Replacement Part for the 'Knob' That Locks the 'Black Plate Under the Arms' in Place

The Beogram 8000 that I recently restored had a broken knob that locks the black plate under the arms in place. Its locking lever had broken off:

The broken part is shown on the left, together with an intact part on the right. I never really liked the design of this knob. It always seemed a bit of an afterthought, the way it slides into the plate, and considering how difficult it can be to turn it at times when it gets stuck. The usually damaged screwdriver slot is a testament to these issues:

So I was motivated to design a replacement that is a bit more functional. What I came up with is a two-component solution bolted together with a black M3x6 hex head screw countered by a square nut:

This part is now available at the DKaudiolover store.

Installation is straightforward: Insert the lower part into the orifice of the plate:

And then install the top part with the bolt:

Make sure the alignment features of the top and bottom parts catch before the bolt is tightened. This shows the installed part from the bottom, revealing the square nut in its recess:

After installation, the knob can be turned with a 2.5 mm hex driver. The integrated position indicator makes it easy to lock the plate properly after installing it:

Unlocked:

and locked:

Beolovely!

Beogram 4004 Type 5526 - Restoration Project - Initial Assessment and Cleaning

2026 seems to be the year of the Beogram 4004 turntable...restorations that is.

This post begins another nice Beogram 4004 restoration project.  

Here is my assessment.

The Beogram is in nice shape and very clean.

The Beo4 remote control pictured next to it is because this Beogram 4004 will be getting a Remote Commander that is paired to the Beo4 controller.

The middle, top of the dust cover has a rather noticeable scratch.  I will try to buff it out so it isn't so prominent later.  This Beogram might end up getting a new dust cover from dksoundparts.

The keypad looks nice as well as the other turntable deck components.

The inside of this Beogram 4004 also looks to be in really great condition.
Of course there is the usual floating debris of disintegrating transport lock plastic material.

Everything else looks great though.

The tangential arm assembly looks good.

I removed all of the transport lock assemblies so I can take out the floating chassis components to work on them.

The main circuit board and the output/remote control board look good...ready for restoration.

Here is the cleaned up cabinet and the removed nuts and bolts.

...and here is the removed floating chassis assembly.  I will start the restoration work with that set of components first.

I did not include any pictures of the DC platter motor for this Beogram.  That is because this Beogram 4004 will be getting a Beolover Sync Drive platter motor.  

In the next post I will start disassembling, cleaning and lubricating the floating chassis components.

Beogram 8002 (5633): Complete Restoration and Upgrade with Beolover Internal RIAA Pre-Amplifier and Commander Remote Control

Last year, I was offered a Beogram 8002 (Type 5633) in very nice original condition by its original owner. I did not hesitate to buy it! This post details the work done on this Beogram to return it to its original glory and like-new performance. I also installed the Beolover Commander Remote Control for Beogram 8000 and 8002, as well as the Beolover Internal RIAA Pre-Amplifier for Beogram 8000 and 8002.

This shows the unit after I completed my work:

This Beogram 8002 is now available for purchase at the Beolover's DKaudiolover store.

Let's see what it took to get there:

This shows the unit after I put it on my bench:

This unit was in very good cosmetic condition with a mostly unscratched original hood, an almost flawless platter, and very nice aluminum surfaces:

Even the veneer panels were almost pristine with excellent corners:

I put the unit into 'service position, i.e., I removed all the vital parts from the enclosure and set them up on my bench:

First, I focused on rebuilding the main PCB. This shows it extracted in its original condition:

I removed the microprocessor can and replaced all the electrolytic capacitors:

I replaced the period-unique 4-legged original 2200uF reservoir capacitor with the Beolover 4-Pin 2200uF Reservoir Capacitor for Beogram 8000 and 8002. This shows old and new in direct comparison:

And here is an impression of the Beolover part installed:

There was one more electrolytic capacitor that needed replacement: The decoupling capacitor next to the microcontroller in the processor shield can:

I opened the can up:

The capacitor is under the small add-on board. This shows it lifted up, revealing the (gold colored) cap:

This shows it replaced with a modern type:

Note that the negative end of this capacitor is soldered on both sides of the board, i.e., it also functions as a ground via.

Next, I focused on the two electrolytic capacitors on the small PCB that connects the voltage regulators for the 5V and 15V rails:

I replaced them with modern types:

Then I replaced the output relay. They often have oxidized terminals inside or get stuck:

I replaced it with a modern encapsulated replacement:

I also installed a (red) switch that allows connecting the system and the signal ground in case there is a hum issue:

The final capacitor to be replaced was in the transformer block. This shows it opened up, revealing the original non-polar electrolytic motor phase capacitor::

The red part on the left is the Beolover Motor Capacitor for the Beogram 8000 and 8002. It uses modern multilayer ceramic capacitors, a much better solution for a non-polar capacitance to shift a motor phase. This shows the original capacitor removed and the Beolover replacement connected to the original leads:

The Beolover capacitor is designed to accommodate both 50 Hz and 60 Hz Beogram versions. Simply solder one of the leads to the terminal labeled 'COM' and the other to the 27uF terminal for US 60Hz versions or to the 39uF labeled terminal for 220V 50Hz versions. Once soldered to the leads, the part fits neatly next to the PCB that holds the mains fuse:

Now it was time to pop up the carriage to clean the usually lubricant-encrusted components responsible for the carriage motion. This shows the carriage liberated and the parts ready for the ultrasonic cleaner:

While the carriage is up, it is the perfect moment for replacing the tracking sensor light bulb with a Beolover Tracking Sensor LED Light Source for Beogram 8000 and 8002. The first step for this procedure is liberating the four wires that lead into the tracking sensor housing. They are secured in place with a small rubber ring placed on one leg of a split post through which the wires are fed.

After removing the rubber ring, the wires can be pulled out:

The next step was removing the small metal plate that shields the tracking sensor from ambient light from the top. This shows it still in place:

After lifting the front end above the small plastic peg, the lid can be slid out to the left, and the photoresistor and bulb become visible:

The small board can be pulled out with suitable pliers or strong tweezers for accessing the solder pads of the bulb:

Here is a view from the front:

I unsoldered the bulb. This shows the liberated bulb together with the Beolover LED replacement:

The LED board is soldered to the same pads that supplied the bulb:

Make sure the LED faces the photoresistor if you try this at home!...;-). This shows the small PCB back in place:

Then the cover can be re-installed:

The final step is putting the wires back into their original position and reinstalling the small rubber ring to hold them in place:

While the carriage is up, it is the perfect moment for adjusting the vertical arm parallelism to get the tone arm parallel to the sensor arm:

In the meantime, the removed parts came back nice and shiny from the ultrasonic bath:

I reinstalled the parts and put the carriage back into place. Then it was time to adjust the lateral arm parallelism using my recently developed Beolover Arm Alignment Tool for Beogram 8000 and 8002:

The tool makes it easy to get the arms adjusted perpendicular to the carriage rods.

Next, I focused on the keypad, which always gets the light bulb in the <</>> assembly replaced with an LED. In this case, I also installed the Beolover Commander Remote Control for Beogram 8000 and 8002:

Check out the video that is posted under the above link for details on how the Commander is installed and how it works. 

This shows the LED installed in place of the light bulb. in the <</>> assembly:

Since the bulb runs on 15V, the LED needs a current-limiting resistor in series:

Make sure this resistor is installed in the approximate location as shown above if you try this at home. Otherwise, it may be in the way when the PCB is clipped back into place behind the keypad.

I plugged everything back together and did the <</>> voltage adjustments per the service manual. The screws in the black <</>> housing need to be adjusted to get 650mV for both << and >> directions when the buttons are not pressed.

I also did the tracking sensor feedback adjustment. This shows the LED in action:

The feedback needs to be adjusted so that the platter rotates 2-3 times before the carriage starts moving after the needle hits the record. This can be adjusted with the small screw on the right side of the tracking sensor housing. It moves an aperture inside the housing, and with this, determines at what point of the arm deflection enough light falls on the photoresistor to cause the carriage motor to come on.

The other upgrade for this Beogram 8002 was the installation of the Beolover Internal RIAA Pre-Amplifier for Beogram 8000 and 8002:

This shows the board installed:

It is designed to connect directly to the solder pads where the output wires for the left and right channels are connected on the ribbon cable:

Simply unsolder the wires:

and then bolt in the board and solder the four vias on the RIAA board to the clean solder points:

This post gives more detailed info about the installation process.

The latest iteration of the RIAA board features a set of DIP switches that allow routing the output signal with amplification and without. That way, a Beogram fitted with the RIAA board can be configured for use on both the high-level inputs of modern amplifiers and 'devices', as well as on phono inputs of vintage amplifiers.

At this point, everything was in place for a first test-spin. I put on one of my favorite Kraut-Jazz albums, "House-Boat" by Volker Kriegel. This very crisp-sounding album was released on MPS Records in 1978 (MPS 15.535). The perfect music for happy afternoons fixing Beograms!...;-). The Beogram in service positon performed very well:

Now it was time to work on the enclosure. Like most Beogram 8000 and 8002 units these days, this unit also had loose aluminum panels. I glued them back into place after removing all the degraded double-sided tape remnants:

The small shield attached to the black panel under the arms had also come loose:

I reunited them with some modern double-sided tape:

After playing a few more records, I decided it was time to put everything back into the enclosure.

Here are a few nice pictures of this fully restored Beogram 8002. Enjoy!: