Beogram 4002: Final Tasks, Adjustments & Playing Records

It is time to finish up this Beogram 4002 Type 5513 project. As a continuation of the corrosion damage repair I am replacing the 5-pin DIN phono plug.

Here is a nice reference diagram Beolover created a while back that shows the audio path from the MMC cartridge connector to the 5-pin DIN plug.

I like this diagram because when I am replacing the phono cable plug this shows the phono signals I check continuity on from the Beogram output board connector (P9) to the front of the plug.

Here is a picture of a continuity check for the phono right channel from the phono DIN plug to the output board P9 connector.

I installed a REAN 5-pin DIN replacement plug that has gold contact pins.

A note to other DIY folks that do this - Some of these Beogram phono cables have a cable diameter that makes installing the REAN rubber boot extremely difficult. The fit is really, really tight.

Another phono signal related change I made was to return to the output board and install a grounding switch between pins 5 and 6 of the P9 connector. That is signal ground and shield ground respectively. The Beogram 4002 units come with a separate grounding wire so owners can connect their Beogram chassis ground to an amplifier's chassis ground should there be hum in the signal path.
This grounding switch eliminates the need for that extra grounding wire as the switch can be flipped to short the two grounds together in the Beogram if needed. A nice option and the switch is easy to get to.

One last electrical task is to install the two RPM indicator light replacements (33 & 45 RPM lights). This upgrade of incandescent lamps to the Beolover LED replacement is not for cosmetic reasons. Beolover's ongoing testing of Beogram 4002/4004 DC platter motor stability has shown a positive measurable effect of the LED lamp assemblies over the incandescent lamps. So we recommend them on all of our Beogram 400x restorations.

One weak part of the Beogram 4002 design are the mounting clips for the RPM indicator panel into the control panel. The mounting clips are a hard plastic that often becomes brittle over time and cracks. This unit had a couple of hairline cracks so I applied some preventative patches.

I started the final reassembly of this Beogram unit which includes the service manual adjustments.

The first adjustment is for the Beogram platter height so that the distance from the top of the fixed arm (and tonearm) is 23mm from the surface of the platter. That adjustment is made using the large nut on the platter hub.

The tonearm lowering limit and pickup arm length adjustments are next.

That is followed by vertical and horizontal arm parallelism.

While the platter belt is still removed I adjusted the tangential arm sensor.

Now for the deck panels and the platter position adjustments.

Everything looks good. I performed the arm balancing adjustments earlier so the final adjustments are for the platter speed trim pots.

This Beogram is cleared for record play. I'll give it a listen as I document this blog post :-).

It looks like this Beogram is ready to go back home to Houston. Now where's my copy of "Houston El Mover"?

Beogram 4002 Type 5513: Some Cabinet Work

This weekend I worked on getting the Beogram 4002 re-assembled with its cabinet trim and deck cover. I removed the rosewood trim so it would be out of the way and not be susceptible to accidental damage during the other restoration steps.

The rosewood trim attaches to a metal frame that slides out to unlock and slides in to lock the Beogram 4002 cabinet. The metal frame has five guide washers that are almost always broken on the Beogram 4002 units. This one was no exception. The guide washers are a special designed part as shown in this earlier Beolover post.

Here is this Beogram fitted with the Beolover 3D printed guide washer replacements.

At first you might think these can just be refitted with some flat washers from the hardware store. Why buy the special printed parts. I can tell you these guide washers make a big difference in properly assembling the Beogram cabinet. As you can see in the Beolover blog post, the guide washers mount in place to provide a proper guide for the cabinet locking frame to slide along.

As I was attaching the cabinet trim/lock I noticed the frame was separating from the rosewood along the front.

This had to be epoxied before I could continue. It is not a good idea to glue it in place. Glue can be messy and before you know it you have a crisis on your hands. Be safe and properly remove the trim piece to work on it independently.  I cover all of the rosewood with good painter's tape so I don't have to worry about scratches or glue residue on the finish.  This picture shows the glue areas ready to receive the epoxy.

You can't have too many clamps. A couple of years ago I found these little miniature clamps like the big ones I have in my workshop. They are great for small things like this.

For this type of gluing I like to use a slow drying epoxy so I don't have to panic in getting excess glue wiped off and making sure the clamps have everything aligned.  I let this dry overnight.

The next morning the trim/locking piece was ready to use. Now I could finish attaching it to the cabinet with the five guide washers.  It fits good and looks good.