Beogram 8000: Packing for Shipment Home

On my previous Beogram 8000 project I packed the turntable using an original Bang & Olufsen Beogram 8000 shipping box plus an outer box. Here are some pictures of that shipment.

In an amazing feat, the shipping company managed to damage the Beogram during shipment. There was no real visible damage to the shipping box so it was assumed that the box was dropped straight down and flat. The impact caused the transform upward so that it knocked the metal door above it off its hinge. On the downward stroke it broke the main Beogram PCB.

Fortunately I had a spare Beogram 8000 main board so I was able to repair the damage. The door hinge was not broken so I reset that. The shipping company insurance paid for all of the damage and shipping costs.

For the return shipment I did some rethinking about the packing. The monster packing box had failed to protect the Beogram in this case and that was with the B&O original Beogram inner box. So how do I improve the odds?

One thing I decided was the double boxing in this case made for an extra large shipping box and was probably difficult to handle. That isn't really an excuse but if I can improve that it should lessen the chance of a drop.

I decided to go to a custom, single box rather than the original B&O box inside an outer box. The new box however is double-wall. Twice the thickness of a normal cardboard shipping box.

The other issue was with the super dense, three inch thick foam. It is very strong but doesn't provide enough cushion. The new box would have dense, polyethylene foam glued to the inside walls and floor of the double-thick cardboard box.

I also decided to custom cut the polyethylene foam to fill the cavities under the dust cover and tonearm compartment lids.

To protect against any impact force driving the transformer anywhere I wrapped the tonearm compartment door completely before wrapping the whole Beogram with firm eggcrate foam.

I used a nice strong vinyl record shipping box to pack up the Beogram platter and put that on top of the foam wrapped Beogram.

Here are some pictures of the new shipping box packing. Of course it begins with locking down the floating chassis for shipment. Here is one of the three lock down screws in the lock position.

Next is making the foam insert to hold down the sub-platter. Note that there is a part of the foam insert that goes into the back of the case where the tangential arm moves. That foam piece prevents any arm movement during transport.

The next picture shows the packing stretch wrap around the Beogram (under the lids and over the lids).  That lid is not able to move at all now.

Now the Beogram is wrapped with a clear plastic bag then wrapped twice with firm eggshell packing foam.

The securely wrapped Beogram is placed in the double-thick box that has the polyethylene padding. Extra polyethylene foam blocks make the fit tight and create storage compartments for anything else included in the shipment (i.e. phono cables).

The platter box is placed on top then covered with another firm foam pad.

The top polyethylene protective foam sheet is placed on top of all of that and the shipping box can be closed up.

This packing method worked out very nice. The overall smaller box dimensions made for an easier box to handle and reduced the shipping cost by $10. I am happy to say this time the Beogram made it safely back to its owner.

For this latest Beogram 8000 project I am using the new shipping box method as well. Another double-thick shipping box with the same foam padding. I changed my wrapping a little bit on this one. With the previous shipment I used packing tape around the eggshell packing foam. This time I used stretch wrap. That made for a little tighter wrap of the Beogram so I had to add another polyethylene foam wall. That resulted in some nicer mini compartments.

The platter box still goes on top of that followed by another eggshell foam piece and the top polyethylene sheet.

This Beogram is safely packed for the journey back home.

Beogram 8000: FOD Bites Me In the ***

Having a little experience in the aircraft industry I know about the acronym FOD (Foreign Object Debris). This post is an example of why the term exists and how it can even apply to turntable restoration.

In my recent Beogram 8000 restoration I was extremely happy with the final results and shipped the turntable back to the owner. Although the packing was as good as it could be there was undoubtedly a lot of vibration during the truck journey. When the Beogram 8000 arrived back home the owner noticed the tonearm was drooping. That should never happen. After failed attempts to solve the problem by phone the Beogram had to be shipped back to the workbench.

As soon as it arrived back I unpacked up the Beogram 8000 and saw that the tonearm was still drooping down instead of level with the fixed arm.  I put the Beogram into service position and the tonearm popped back into its normal position. That always happens doesn't it?

The question is what could have been causing the problem?  I started examining every detail of the arm lowering and raising parts. It is natural to suspect the arm control solenoid and some electronic control but this Beogram had extensive bench testing without any such incident. I was pretty sure the problem was mechanical.

Here are some pictures of the Beogram 8000 arm lowering/raising parts.

I exercised the arm lowering and raising manually to see if I could feel any restriction but everything was nice and smooth operating. I also powered up the Beogram and operated the Play/Pause/Stop functions a number of times while observing the solenoid action. No problems there. I wondered if something in the tonearm linkage just slipped a little during shipping and now it is all okay.

One new thing I did notice about this Beogram was that the tangential arm carriage drive was noticeably louder going forward than returning to the parked position. Of course I remembered that this turntable had a broken tangential drive shaft bearing. I had reversed its position and it worked fine while it was here earlier. I didn't discern any difference in the tonearm scanning (noise) at that time. However that damaged plastic lip on the bearing must be the source of why one scan direction is now louder than the other.

So while I hadn't found the source of the tonearm drooping problem I felt I needed to go ahead and fix this tangential drive noise issue. I had one spare drive bearing remaining in my stock so I grabbed it and prepared the install. This operation means taking the tangential drive off its rails and flipping it over to get to the bearing. While there I can also examine the tonearm lowering and raising components from another angle.

This is where I discovered the prime suspect of the tonearm problem. A piece of FOD was visible near the arm control lever.

That piece looks familiar! I looked at the tangential drive bearing and sure enough, that is the piece that had broken off the bearing...probably years ago.

If that small piece of plastic had shifted into the slot that the tonearm lowering bar slides in it could easily have caused the problem where the arm would not fully raise. I can only surmise that is what happened but it seems highly likely. The Beogram hadn't and still doesn't exhibit any bad behavior with the arm functionality. I don't think it is a coincidence that this plastic piece was in the location I found it and it not be the prime suspect.

I installed the new, fully intact, spare drive bearing and the tangential arm scanning operations are smooth again.  They operate with only the expected, soft whirring of the motor.

Now for the important lesson (re)learned about FOD. Seeing that the original bearing had a broken piece off the lip I should have done a more thorough inspection of the Beogram to search for it. I had just assumed it was long gone. On the Beogram 400x turntables where their transport lock bushings are often deteriorated into a thousand pieces I have to do a full cleaning of every part. This incident shows that even one broken piece of plastic debris can cause problems.

I am an optimist though so I take the view that this was a good learning experience and this Beogram needed the drive bearing changed anyway so it worked out good. It is time for a quick play test then I will ship it back home again.

Beogram 8000: Returning Home

Today is the big day. It is time to pack up the Beogram 8000 and ship it home to its owner. The turntable has been playing beautifully the last few days with very heavy use and no signs of any intermittent behavior. It was definitely a good thing to install a brand new phono muting relay.

After all of that work it is important to properly pack units up for shipping. Especially turntables. A loose item here or there can cause extreme damage. Everything must be locked down and secure.

Bang & Olufsen has long been using a floating chassis for their turntables and provide a chassis lock down mechanism for transporting them. On the Beogram 8000 (and 8002) there are three lock down bolts under the main platter. The bolts are screwed down out of the way when the turntable is ready to be used. For transport the bolts are backed out and through a mounting plate. When through a hole in the mounting plate, the plate is slid over and the bolt is tightened against it so the floating chassis cannot move.

This lock down should be performed even if transporting the turntable in your vehicle to deliver it yourself.

The phono cartridge should also be removed from the tonearm at this point. To secure the tangential arm assembly and the top platter, B&O provided a special molded styro-foam piece. It holds the top platter securely and slides onto the deck of the Beogram with a tab to block the tangential arm assembly from moving.

The dust cover lowers on top of the platter packing to protect the dust cover and to hold the platter down so the sub-platter cannot move.

The outside of the Beogram is then protected with a soft, foam sleeve.

Finally, two molded styro-foam blocks slide over the front and back of the Beogram to lock all of the packing in place.

The Beogram and shipping material is placed into its original box which is inside an outer box that has thick foam protection on all sides.

It costs more of course but please don't ever skimp and not use an outer box. That is just asking for trouble. The only time to use just the original box by itself is if you are hand delivering the unit.

The final step is sealing the shipment and applying the shipping label. Then off it goes.

Beogram 8000: Reworking The Phono Muting Relay...Again

Since the replacement of the Beogram 8000 Control Panel board with a spare I had this Beogram has not had any mishaps with unscheduled pauses during record play.  During retesting of this however, the spare phono muting relay I installed is acting up like the original one did. The problem is intermittent but when it occurs the phono signal is not muted when the tonearm is lifted.

This still sounds like a relay problem and I didn't really like the fact that I had to use a replacement for it from another Beogram 8000 turntable instead of with a brand new relay. The problem is the Beogram 8000 output board is designed for a National type relay that is no longer available.

The Beogram 8002 output board it turns out is interchangeable with the Beogram 8000 and the Beogram 8002 muting relay is still available new from my favorite suppliers.

Before swapping output boards and relays I want to do diligence and measure the Beogram Lift signal.

The Beogram 8000 Muting and Lift circuits are related. A Lift command from the processor causes the tonearm to lower or lift followed by the muting circuit engaging or disengaging the phono muting relay.

I checked out the three test points shown on the diagram on my oscilloscope to see what is happening.

The above picture shows the Lift command in red from the Beogram processor. About 2.5 seconds after the Lift signal (to lower the tonearm), the muting relay engages to allow the phono signals to function.

When the tonearm is raised the Lift signal fires again and the muting relay disengages, shorting the outputs together.

I observed this switching function for a while and never saw any problem with it. However, I did see a problem with the muting relay. While the oscilloscope was measuring the Lift signals I connected my DMM to the phono left and right signals to measure the resistance.

Initially, before turning on the Beogram, the resistance measurement between the left and right channels was a short circuit. I measured about 0.4 ohms. When the tonearm lowers the phono signals are opened up and I measure an open circuit. When the tonearm is lifted the left and right channels should return to a short. There were a few times that I observed around 250 ohms to 280 ohms across the channels instead of a short. So the relay contacts are still the problem.

It was time to go ahead and use a Beogram 8002 output board in place of the original Beogram 8000 output board.

Here is the Beogram 8002 phono output board. The following pictures show changing out the muting relay with a new, sealed Omron relay. I also installed the ground switch option on this replacement output board assembly.

Now it was ready to swap the output boards.

The following picture shows the difference between the two output boards when the phono muting is on.

The new relay does a much better job and I feel much better having a brand new relay installed.

The other test point I wanted to measure is the Beogram 8000 tonearm lowering circuit. The damping of the tonearm when it is lowered to play a record is often a trouble spot. Sometimes owners observe the tonearm just dropping instead of slowing lowering. The control of the arm lowering is via an OpAmp circuit that is used to generate a ramp voltage to engage the tonearm lowering solenoid.

This Beogram has been lowering and raising exactly as it should so I captured some measurements to use as a reference. I measured the ramp signal as it reacts to the processor Lift command.

Whew! The Beogram 8000 is connected once again to my audio system where I will exercise it again before sending it home.

Beogram 8000: Final Steps

I was kind of lucky I suppose in finding the intermittent pause culprit on the first suspect. However it was the most likely when reviewing the problem. Even though the behavior was intermittent it lined up with a problem Beolover had on a Beogram 8002 project earlier. After replacing the Beogram 8000 original control panel board with one of my spares -

the result has been over twenty error-free record plays.

Returning to the original control panel board to look at repair options I examined the LDR (photoresistor) devices for the forward and reverse controls.

Visually examining them and testing their resistance with different light sources didn't reveal any problems. These devices can become unreliable over time and exhibit the intermittent behavior I experienced so I decided to apply the repair Beolover did on the Beogram 8002.

I ordered the same LED from Newark and some GL5549 LDR devices from a couple of different sources. Replacing the original lamp with an LED requires a load resistor so I used the 1K ohm value Beolover had set his to.

Using the same parts I was hoping the fix would just be a quick install, test and go operation. Unfortunately I found that these GL5549 LDR devices vary in performance by quite a bit. It took quite a while to find a pair of these new LDRs to match and be around 20K ohms when in place on the board.

After finally finding a couple of acceptable LDR devices to try I mounted them with some temporary glue to secure them in their respective mounting slots.

I prepared the control panel board for re-installing into the Beogram. That included adding my little LDR test connector. This time I used 30 gage hook-up wire so the test connector can be left in the control panel. I matched the wire colors to what the Beogram 8000 colors are for the LDR measurements. That makes it easier to remember later if I have to retest the LDR voltages.

The connector is also a female connector so I don't have to worry about anything shorting by it when I leave it in the Beogram.

Testing the reworked control panel board with the new LDRs was interesting. I ended up having to re-adjust the position of one of the LDR devices. That is why I use glue that isn't permanent. Eventually I was able to get the forward and reverse LDRs adjusted within the 600mV - 700mV range necessary for successful operation. The service manual originally asked for 620mV but later updated that value to 650mV. I talked to another Bang & Olufsen technician who told me a solid value between 600mV and 700mV is sufficient.

As you can see in the picture above, the adjustment for a working forward and reverse operation resulted, again, in quite an imbalance in the adjustment screws of the control panel board. The voltages are stable though so I am going to run another play test with this board just to see what happens.

For this project though I am inclined to go with the replacement control panel board that I ran the twenty successful record plays with. The forward and reverse LDR controls are closely matched on that board and I feel will be more of a sure thing. This replacement repair is looking good but I will feel better about it if I can do a long term test with it.

There is one more issue that cropped up during the play testing of this Beogram 8000. Another intermittent problem but one that was easily recognized. A couple of times after a record completed play I noticed that the phono mute did not occur. That means the Beogram phono mute relay is acting up. This picture shows where the muting relay is located. It is easy to get to but does require opening up the Beogram case again. Oh well.

I hadn't planned on replacing this relay but since it has come up I asked the owner if he would like the phono grounding switch to be added. This is a convenience option that Beolover has been doing on Beogram 400x and 800x turntables. The added switch gives a user the option of setting the turntable up as it is originally or shorting the phono signal ground to the Beogram chassis ground.

This is a nice feature for Beogram owners that use the turntable with a non-B&O amplifier. I pair a lot of my Beogram units with my Yamaha C2a, C2x and C-70 preamplifiers. Those pre-amps support two turntable inputs but require using RCA jacks. When I add the DIN to RCA converter I get a hum in the phono signal unless I attach an extra grounding wire on the adapter to the amplifier chassis ground lug. With this switch added to the Beogram I can short the phono signal grounds to the chassis ground in the Beogram and not need the extra grounding wire on the cable adapter.

It's doesn't seem like a big deal but it is nice to have options so we are adding the switch to this Beogram.

First I need to removed the faulty muting relay.

This muting relay is different than the one in the Beogram 8002 turntable where Beolover was able to replace it with a new Omron sealed relay device. That relay pin layout is not a match for this Beogram 8000 output signal board. My only option here is to take a newer output relay from one of my later model Beogram 8000 spares.

If I didn't have a spare I would have removed the clear plastic cover and tried to clean the relay contacts. That still might not have solved the problem if it is in the relay coil.

I installed the new muting relay and then attached the grounding switch.

I used some hot glue in the gap between the output board case and the switch case. This helps secure the switch.

Now it is back to the record play testing again. Success of these tests will result in this Beogram being packed up to return home.