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Beogram Commander Remote Control: Maybe This is the Final Version!..;-)

This is a follow up to my recent post about the redesigned Beogram Commander remote control board, which now works in both (DC-motor) Beogr...

Beogram 4002/4004 Restoration

This video shows how to prepare and double-box a Beogram 4002/4 for shipping (please make sure to also read this update about securing the carriage for transport, and this post about how to secure the arms with a reproduction B&O style elastic support):



This post shows how to place the cartridge into a Beolover MMC shipping container, which will be supplied along with the Beolover double box.

Control your Beogram 4002 or 4004 remotely:


Beolover Commander Enables Control of Beogram 4002 or 4004 with the Beosystem4 and the Beo4 Remote


This is a list of key posts about the restoration of Beogram 4002/4 series turntables:

This post gives an overview of a complete functional restoration of an AC-motor Beogram 4002.

Beogram 4002 (5513): Cabinet Repair and Guiding Washers Installation

Beogram 4002 (5513): Replacing the DIN 5 Cable with a Cable Featuring RCA Plugs

Beogram 4002 (5513): Power Supply and Replacing the Reservoir Capacitors with a 3D Printed Fixture
The 550x Types have a different reservoir capacitors setup due to the AC motor design. Check this post for details: Beogram 4002 (5503): Exchanging the Reservoir and Motor Capacitors and Recap of Main PCB

Beogram 400x: Cleaning and Re-lubricating the Tone Arm Lift Mechanism

Beogram 400x: Replacing the Tracking Sensor Light Bulb with a Plug-In Ready SMD LED Assembly. This post gives some more information about the record detection mechanism and explains the circuit diagram.

Replacing Incandescent Bulbs in the RPM Adjustment Panel with LEDs. Another post that discusses replacing wavy white background labels in the RPM panel that cause a zebra pattern in the background illumination.

Beogram 4000/4002/4004 Output and RPM relay replacement with custom designed adapter PCBs that drop into the original relay's solder spots. Available for both National and Siemens type relays that were used across the Beogram 400x range.

Beogram 4002 (5513): DC Motor Restoration
This post explains how to restore the DC motors of the 551x and 552x types. The how-to video for oil infusing the oilite brass bearings is posted here. An additional failure mode of these motors are shorted spark snubbers. Beolover offers motor restorations including 24 hrs RPM stability testing. Just send an email or use the contact form to the left.
Beogram 4002 (5513): DC Motor Restoration and Yet Another Exciting Aspect of Achieving RPM Stability. This post discusses an aspect of the DC motor control system, that can lead to additional RPM stability problems. Sometimes the pickup coils for the RPM feedback get damaged during restoration of these motors. See here for an example.

Beogram 4002 AC Motor Restoration (Type 550x): This post discusses the restoration of AC platter motors. This can be necessary if the motor knocking cannot be alleviated by tilt or motor voltage adjustment. Scroll down for a link to motors with belt guides.

Beogram 4000/2/4: Update of Sensor Arm LED Assembly. No More Crumbly Flex-PCB Mess!
This post points to a video that shows in detail how to replace the sensor (detector) arm light bulb with an LED. It also explains how the circuit works, and how to upgrade it for reliable performance.

Beogram 4002 (5513): Replacing the Electrolytic Capacitors on the PCBs

Beogram 4002/4004 Keypad Restoration
Most Beogram 4002 and 4004 have keypads where at least one or two keys show wear patterns.
This post shows how we fix them for our restorations.

Beogram 4002/4004: 3D Printed Cabinet Guiding Washers

Beogram 4002/4004: Replacement of the Transport Lock Bushings With 3D Printed Parts

Beogram 4002/4004: Replacement of a Broken Cable Clamp/PCB Holder

Beogram 4002/4004: New Belts and RPM Adjustment

Beogram 4002/4004: Sudden RPM Changes - Replacing RPM Trimmers and Relay

Beogram 4004/4002: Tracking Force Adjustment and Zero Force Balancing

Beogram 4002/4004: Adjusting the Tonearm Lowering Limit

Beogram 4004: Characterizing a MMC20EN Cartridge with an Analogue Productions Test LP

Beogram 4002: Signal Path between DIN5 Plug and Cartridge, Plug Replacement

Beogram 4000: Polishing the Hood

Beogram 4002: Keyboard Repair - Detached Backstops

Beogram 4002 (5501): Replacement of End Groove Detection Light Bulb with an LED

Beogram 4002 (5503): Repair of a Cracked Solenoid Lever

Beogram 4004: Installation of Beolover 4002 RIAA preamp (RIAA preamp needs a small modification to work in a 4004)

Some faults and their repair:

Beogram 4000 (type 5215): replacing sensor arm photo cell with modern one (it is a similar procedure for the 4002/4)

Beogram 4002 (5513): Repair of a Broken SO ('Shut Off') Switch

Beogram 6000 (5512): Dead IR Diode in Carriage Position Sensor (same procedure for 4002/4s)

Beogram 6000: Carriage always runs across the platter and RPM switches to 45 after START

Beogram 4002: Too Early Arm Lowering and RPM Change During START

Beogram 4004: START Key Not Working

Beogram 4002: Non-Working End Groove Detection - Repair of a Detached Carriage Position Sensor

Beogram 4002 (5501): Random Stop Issue Fixed - Defective Photo Resistor in the Spindle RPM Sensor

Beogram 4002 (5501): Repair of a Strange Fault Caused by a Shorted Diode D6

Beogram 4002 (5503): Unit Switches Immediately to 45 RPM After Pressing Start

Beogram 4004 (5526): Adaptation of a 1985 Platter DC Motor and an Exciting New Motor Failure Mode The failure mode described in this post is a short between spark snubber wiring and one of the coils on the rotor of the motor.

(This post describes how to replace the automatic gain control bulb in the AC platter motor oscillator circuit with a resistor and a diode clamp; 4002 AC motor versions have the same circuit like the 4000)

MMC Cartridge Repair:

We do not do it, but you can get your cartridges professionally repaired/rebuilt here:



6 comments:

  1. I recently acquired a B & O Beogram 4002 before the music teacher threw it in the trash at the school I work at. These are new to me, but I have fixed other turntables and wasn't afraid to get my hands dirty. It seems to work just fine, but the stylist won't drop. I can manually move the solenoid and the mechanism works fine tommy knowledge. I fear it isn't getting the "signal" to engage.

    Suggestions?

    By the way, I love your YouTube videos and learned a lot while researching the answer to my problem. If the answer is in there please direct me to the correct video. I was able to do other "fine tuning" on the machine thanks to your videos.

    Please let me know what you think.

    Randy Schuster
    Audiophile

    ReplyDelete
    Replies
    1. Hi Randy, I am by far not as good as restoring these as beolover is. But as I recall the solenoid motion is dampened by the air pressure in the valve to it's right.there is a screw situated on top of it, that if I understand it correctly allows the air to get out of the cylinder. Open it should ensure that the arm goes down. It seems to be a common problem when they are not in use. Taking the the cylinder appart and treat them with a bit of oil helps. Again I am no technician, but it worked for me.

      - Jens

      Delete
    2. Hi Jens
      Interesting. I have the same problem. Could you post a picture of the exact screw you are mentioning?
      Thanks from The Netherlands says Matthé

      Delete
  2. Hi - I recently adopted a 4004 turntable (and beomaster 2400). The 4004 seems to work just fine but; the speed slows for a couple of songs near the middle portion of album play. This pattern repeats.
    Any ideas? Thanks - M

    ReplyDelete
  3. Fixed. Platter was rubbing on a screw head on the tonearm transport. Raised platter. Thanks for the good videos on these, they helped me understand how to get in and delve.

    ReplyDelete
  4. Back! It was not a screw head but a red plastic application of some sort.

    ReplyDelete

Comments and suggestions are welcome!