[Mark-sf]

Renfield wrote:

Reply to Mark-sf On 1, 2, No! 3. Randomly 4. I’m using DIN, that’s what my my Beomaster 4400 has 5. What is R112/212? Kindest regards Mats

Mats, For the sound to come from both your speakers but not be controlled by your volume control is highly unusual and could only occur if the act of playing a record was injecting/disturbing the power amp section of your 4400 directly. I would ask that you try playing a few records with the volume full down and then trying again with the DIN cable unplugged and report your results.

As to R112/212 there are adjustable resisters (trimmers) that are accessed via a screwdriver through the bottom labeled Phono L & R.

[Mark-sf]

While I have not heard of this issue, there are some questions that can narrow it down.

1. Does the sound occur only on one channel?
2. Does the sound vary with volume; for example, if the volume is turned way down is the sound soft?
3. Does it occur at the same position on the record or randomly?
4. Are you using the DIN or RCA jacks?
5. Have you tried cleaning or replacing the two trimmers R112/212?

[Mark-sf]

By back panel are you referring to the black grill that covers the connections? If you are it is only held by gravity. There is a stop piece attached to the underside in the middle of the grill piece that might have gotten stuck down.

[Mark-sf]

If it is of Type 58xx I would replace the belt and clean the pulley. If the 54xx you also have an idler wheel to clean. You can find the proper replacement parts at Beoparts-shop.com.

[Mark-sf]

Can you remove the platter and check whether the spinning is stopped by the motor spindle stopping or the belt slipping on the pulley because the platter is hung up?

[Mark-sf]

Do you get the hum when you turn off FM Stereo? How about any other inputs?

[Mark-sf]

Can’t say I remember seeing your problem, but would start by replacing the electrolytic cap in the solenoid circuit and cleaning the contacts under the plastic cover.

[Mark-sf]

Did you tighten the turntable transport screws and remove the platter for your transport. If not its bouncing could have caused issues. The mute switch may have been damaged. Have you tried the tape deck?

[Mark-sf]

You should start by checking the power supply voltages and the electrolytic capacitors.

[Mark-sf]

It sounds like the End of Travel switch is not engaging early enough. This can be either the adjustment of the plastic optical right angle piece that  engages it or the parallelism of it to the threaded rod that the arm moves on. You should also clean its contacts.

[Mark-sf]

I can’t tell from your picture but the correct orientation is marked on the board.

[Mark-sf]

You do not apply oil to the bearing. It needs to be infused in a vacuum. My experience is that they are still the source of your noise.

[Mark-sf]

The motor was considered a single part so B&O did not publish the control-board schematic. What is the nature of the problem you are experiencing. Most of the time its the bearing drying out not an electronic issue.

[Mark-sf]

That may be an old Soundsmith MMC cartridge as they used to make them with gold-tone cases. They are a B&O licensee.

[Mark-sf]

John, great to hear you were successful and the forum proved valuable. Enjoy!

[Mark-sf]

Glad to hear it is now working. Yes, if the arm is at an angle when tracking, that means the shutter is not properly adjusted. Please follow the procedure in the service manual and everything should be fine. If you find you are at the adjustment stop, then the shutter clamp around the base of the arm has been moved and can be mechanically adjusted to give you a new center point.

[Mark-sf]

Specifically changing from foam to rubber will alter the low frequency resonance changing the bass response.

[Mark-sf]

You lift the platter off and place it around the sub-platter and motor pulley.

[Mark-sf]

Troubleshooting FM sections is difficult without the right test equipment. If you’re getting a hum I would first focus on whether all of the power supply voltages are correct before changing any VRs. It really helps to have a signal tracer or at least a scope so you can check the RF section.

[Mark-sf]

Glad you are making progress. That antenna is for AM reception though it will work. B&O supplied dipole wired one or one with two hinged rods for FM like this

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