Beogram 4002 Type 5513: Return to the workbench for a new phono cartridge mount - Conclusion

The new Beolover replacement phono cartridge mount is installed now in this Beogram 4002 Type 5513 turntable.

This type of restoration is always fun. My very first collaboration with Beolover was on one of my Beogram 4000 turntables where we decided there needed to be a replacement phono connector so the repair didn't have to use a donor Beogram. Since Beolover created this phono connector part it has saved many a Beogram turntable I am sure.

Certainly this Beogram 4002 Type 5513.

Here are the components again -

I like to replace the phono wires on this type of repair. I use color coded 36 awg wires.

Preparation for the repair means tinning the leads of the new wires and the connector assembly contacts.

I start with the two inside wires and finish with the outside wires.

Note that the bottom part of the Beogram phono connector assembly reuses the original connector part.

Before I join the two halves of the phono connector I use a some Aleene's Tacky glue to hold the wires in place and act as kind of a strain relief while I work on the repair.

This is why you keep old MMC phono cartridges...even if the the cantilever and stylus are gone.
They are perfect for this repair in making sure the phono cartridge assembly is put together correctly and inserted just right into the tone arm. Aleene's Tacky glue is used again on the joining of the two phono connector halves.

I also use a little more of the Aleene's Tacky glue inside the tonearm when I reinsert the phono connector assembly.  That insures the phono connector is secure but it could still be taken out again in the future. You don't want to use something permanent like epoxy here.

Now I just had to connect the phono wires to the signal transfer board and this repair will be done.

That concludes the Beogram 4002 Type 5513 phono cartridge connector repair.

Because this repair required so much handling of the tonearm I will have to go through all of the service manual tonearm adjustments again to make sure this Beogram is ready for use again.

Hopefully most of the components will still be adjusted correctly but they still have to be checked.

Beogram 4002 Type 5513: Return to the workbench for a new phono cartridge mount

With the third Beogram 4002 Type 5513 delivered to Houston the number two Beogram came back to my workshop. It is suffering from a broken phono cartridge connector on the tonearm.

This type of problem is common on the Beogram 4000 turntables (as they are the oldest in the series) but is not unheard of in the Beogram 4002 Type 5513.  I ran into a faulty phono cartridge connector on a Beogram 4002 Type 5513 back in 2017.

This problem would be a huge problem for an owner and require stealing a good connector off another Beogram turntable if it weren't for Beolover having a replacement part for it.

I will use the Beolover replacement part to repair this Beogram 4002 turntable.

First off I need to prepare the Beogram for the new phono connector.

That means removing the tonearm by unscrewing the two mounting screws that attach it to the tonearm base assembly.

The aluminum tonearm tube pulls out to expose the phono wires and a small transfer board. The transfer board is where the color coded wires from the phono connector connect to the very thin wires that take the signal through the tonearm base.

I am using a small mirror in the two photos below to show the top and bottom sides of the wiring transfer board.

After desoldering the phono wires from the board the tonearm assembly can be removed.

I performed the usual boiling water to ice water trick to loosen the glue that holds the tonearm cartridge connector inside the aluminum tube.  That let me push the connector out of the tube so it can be repaired.

Unfortunately I don't have the Beolover replacement phono connector in my stock of Beogram parts so I quickly ordered one.

In the meantime....continuing the repair preparation, I turned the tangential arm assembly over so I can easily get to the wiring board.  When the replacement phono cartridge connector arrives I will install new phono wires from the new connector to the transfer board.

It shouldn't take long to reattach the wires and this Beogram will be ready to go again.

Beogram 4002 (5513): Repair of Bent System Ground Terminal

After installing my new BeoloverRIAA pre-amplifier design in the Beogram 4002 that I just finished up, I set out to put the enclosure back together and bolt on the hood when I realized that I had completely forgotten about the bent and damaged system ground terminal in the back:

It turned out that I needed to cut the bold off with a saw since the threads were too damaged to get the  rusty nut off that was installed. After getting the bolt out I installed a new 3 mm bolt with the appropriate insulating shoulder washers:

O.k...it seems I am done now! Beolove is in details! Time to ship this 4002 back to its owner!

Beomaster 8000: Repair of a Broken Phono Jack with a 3D Printed Insert

The input jacks (sockets) of the Beomaster 8000 are weakly designed. They are made from a plastic that gets brittle over the years, and frequently the tabs that fix the jacks in the socket panel break off when a phono or tape plug is inserted. When that happens the jacks fall into the panel.

So far the remedy was to obtain a replacement from a carcass...a saddening thought. Beolover has a no-carcass policy! Parting out one should really be the very last resort!

Luckily, the 1980s designers of the jacks had a few looks too many at the cheap American cars that were made during this period (remember the Dodge Omni??), and that inspired them to also cheap down their design of these plugs.

To save plastic, they introduced recesses below the jack surface, which probably reduced the weight of the jacks by about 20%. It occurred to me that these recesses could be used to anchor a 3D printed insert, which would restore full functionality and get close to the original looks of the jacks. I made a brief video about the repair procedure (some pics are below):

The STL file of the inserts with printing instructions can be found on my website at www.beolover.com. I will also be happy to supply this part on request.

Here is a pic of the broken jack:

And with the 3D printed inserts in the recesses:

And after re-installing the jack together with the inserts:

It looks and feels pretty much like an original jack...there is a slight irregularity across the surface of the tabs due to the 3D printing raster. Oh well...it is never perfect! We can only strive!

Beomaster 8000: Wire Bridges on Microcomputer Board (#9) and Broken Phono Jack

Before I put the Beomaster 8000 back together for a test-drive in the living room together with his play-pals, the Beocord 9000 and the Beogram 8000, I cleaned and de-oxidized all the contacts on the microcomputer board (PCB #9), and had a look at the inner sanctum, the EMI shielded processor cans. Usually one needs to re-solder the few vias that are on this board, since they tend to be poorly soldered...clearly in the 80's the PCB technology was not that advanced, yet. Anyway, what I found in this particular Beomaster was remarkable. Someone already had put in the B&O recommended wire bridges (and then some...), and they were directly soldered to the processor pins. Unbelievable! Here is a pic:

While the soldering appears to have been carried out with some capability, I would never do it this way...the only parts of the Beomaster 8000 that are truly non-replaceable are the microcontrollers that contain proprietary coding, i.e. one would have to extract the code from a working one, if one would want to attempt replacing it with a NOS chip...

Anyway, clearly, this needs to be left as is. I could not risk to expose those rarefied microcontroller pins to another heat-cool cycle. In a way, since the chips survived this assault, this solution is probably the most reliable...several fewer spring based contacts in between the controllers and their slaves...so I decided to just replace the two electrolytic capacitors on this board and move on.

Here is a pic after putting in the caps:

The last thing that needs to get fixed in this Beomaster is a broken phono jack in the 'socket panel' that lost its tabs that prevent it from popping into the panel when trying to plug in the Beogram:

I am working on a creative solution, since not even Dillen of Beoworld.org has this part available.  He said it is rare, since it often breaks...Another day, another 3D print...;-)